Reticular Chemistry and Materials for Water Harvesting from Air Anytime ...

Reticular Chemistry and Materials for Water Harvesting from Air Anytime Anywhere- Omar Yaghi ASU School of Molecular Sciences 1.47K subscribers Subscribe 50 Share Download Save 1,771 views Nov 23, 2021 Professor Omar Yaghi from University of California, Berkeley, delivered the spectacular Inaugural O'Keeffe Lecture "Reticular Chemistry and Materials for Water Harvesting from Air Anytime Anywhere" at ASU' School of Molecular Sciences on November 19, 2021. Established in 2019 by the School of Molecular Sciences, the O’Keeffe Lecture Series honors the scientific contributions of Regents Professor Michael O’Keeffe. It celebrates his seminal contributions to the study of crystalline inorganic solids, his role in the invention of reticular chemistry, and his important contributions to the reputation of Arizona State University as a place for innovative and impactful research. Learn more about Dr. O’Keeffe’s Career Accomplishments: • Regents Professor O'Keeffe's Career A... Key moments View all Transcript Transcript Search in video 0:03 okay good afternoon everybody i'm really happy to see everybody here 0:08 um this is an event we've been trying to put on for over a year and so i'd like to thank everybody for 0:14 your patience i think we all understand what the issues were we finally felt it was safe enough to have this gathering 0:20 and the purpose of this is introduce uh a new event for the school 0:26 this is an event i believe is an important one both for the scientific culture of the school 0:32 and also to recognize the contributions of one of its most important members 0:41 actually i'd like to take a couple of minutes to step back and talk about those contributions and put them in a 0:46 context which i believe shouldn't be forgotten i think we've all heard this expressions 0:52 like standing on the shoulders of giants i actually believe the school of molecular sciences stands on the 0:57 shoulders of the original department of chemistry and biochemistry here asu 1:02 and that builds on a lot of truly outstanding creative work 1:08 that came out of the original department in the scientific rankings actually 1:14 matter asu in chemistry and biochemistry always comes out close to the top 1:20 in 2011 thomson reuters did a study of scientific impact of publications 1:27 and asu was ranked number six worldwide i'd have a head of mit 1:32 head of stanford ahead of michigan and ucla 1:38 he's not watching but not berkeley 1:43 you know that work was done by an incredible group of really powerful and creative scientists 1:50 and there are a lot of them uh for instance and this this group includes peter busick carlton moore 1:56 bob pettit austin angel of course tom and anna and devons and many others 2:03 and so the school is really indebted to this group of people and the person 2:09 who's probably at the top of that list would be mike mike o'keefe was the third most 2:15 scientist chemist in the world in the first decade of the new millennium mike has been doing groundbreaking work 2:22 on the atomic and electronic structure of crystal materials asu for decades 2:28 he's made really important contributions not just in moths i'm not going to summarize mike's career 2:35 today right in fact i'd encourage you to take a look at a beautiful video that's put together by peter and if you don't 2:41 know the link to the video send me an email send it to you but my contributions were they say went well 2:47 beyond just morphs mike wrote a paper on valence bond parameters and crystal chemistry has 2:52 been cited over 6 000 times it was the first to characterize the electronic structure of a meteorite by 2:59 electron microscopy on its own he and john spence of course developed well observed maybe the first 3:05 observations of atomic orbitals and then of course in a conversation with omar when they were discussing some 3:12 structure mike said can you synthesize this thing i almost said of course we can synthesize this thing not knowing if 3:18 we could and of course he did as the first morph and the rest is history 3:25 mike is one of the most one of the best but most humble scientists i think i've met 3:32 he has been recognized i've actually i would say mike is under-recognized actually but he has has received 3:37 recognition he was a bernal distinguished lecturer he had received a world-class 3:42 professorship at kist in korea he won the new newcom cleveland plaza prize in 3:47 triple a s so did omar in 2019 he was awarded the yamanov prize 3:54 along with omar mike has over 100 thousand citations 4:00 and an h index of over a hundred 4:06 the school since the department of course has grown in diversity and grown very rapidly 4:13 to the point where we found that it's putting a strain on the standard weekly seminars right you know how do we find 4:19 uh speakers who uh who are actually broad enough to appeal to the entire entire sms 4:25 community so we decided to split the seminar series into two so we have specialized seminars and there are 4:31 seminars which are reserved for speakers whose work is so broad and impactful that the entire school will be 4:37 interested in it so hence we have the o'keefe lecture series 4:44 mike's work has been so beautiful so broad and impactful that i can't think of a better name to 4:51 go to describe the spirit of this new lecture series and so here we are finally at the 4:57 first one and of course there could be no more fitting person to give the first hokkien 5:03 lectures than than omar professor omar yagi of the university of 5:09 california berkeley you know we often say that people need no introduction and almost only doesn't 5:15 but just in case you don't know omar began his academic career here at asu in 1992 5:22 1999 he moves to university of michigan the robert parry professor of chemistry 5:28 in 2006 the ucla is the chris foote professor of chemistry and since 2012 he's been the james and 5:36 nielty care chair and professor of chemistry uc berkeley 5:42 he's a senior faculty scientist at ron's berkeley lab he's the founding director of the 5:47 berkeley global science institute i have to read all this stuff there so much the co-director of the cavali energy 5:53 nanosciences institute and the california research alliance 5:59 almost obviously most well-known for the invention the design the synthesis 6:04 of moths coughs and many other structures which fall into the larger umbrella now reticular 6:10 chemistry it's not the only thing he's done he's also responsible for the invention of the field molecular weaving and many 6:16 others i have a list right of wars that omar's 6:22 one and it's very long i'm not going to go through them all just pick one or two 1998 he won the solid state chemistry 6:28 award the american chemical society when he was still at asu 19 2009 the material chemistry award for 6:34 the american chemical society the triple a s newcom cleveland plaza prize award winner 6:40 when the royal society of chemistry centenary prize the japanese society of coordination 6:45 chemistry international award the albert einstein world award of sciences he's received the wolf prize the yamanov 6:52 prize and just this year the royal society of chemist sustainable water award which connects to the title at the top 7:01 we really appreciate omar taking the time to come visit us he told me this is the first time he's given a public lecture since the pandemic 7:08 so we appreciate that and we like to recognize the occasion actually by giving omar a little small 7:14 plaque so omar please got a small plaque to recognize this and the plaque has 7:20 the infamous moth five right there there we go so omayagi university california 7:25 berkeley reticular chemistry materials for water harvesting from air anytime anywhere november 2021 the o'keefe 7:33 lecture series so omar thank you for coming please we won't shake hands but you can take this smile for the camera 7:39 [Applause] 7:45 thank you so with that omar please the floor is yours thank you 7:52 thank you ian for that nice introduction and also um introducing the o'keeffe lectureship 7:59 it's real pleasure to be here on many many levels not the least of which 8:05 is uh really to speak on behalf of michael o'keefe and my collaborations 8:12 with him in inventing a new branch of chemistry highly understated but nevertheless i 8:20 will express it in my own in my own words i think it's uh it's also 8:27 really nice of sms to recognize one of its members in this in this way 8:33 and uh i hope that um that this tradition would will 8:38 continue so no surprise the title of my talk is reticular chemistry and more 8:44 specifically the invention of reticular chemistry and the development of reticular chemistry 8:49 but also the outlet of this chemistry one of the outlets among many is the water 8:55 harvesting from desert air and when you can harvest water from desert air you can do 9:02 it anywhere at any time of the year so 9:09 my very first paper at asu is this one it doesn't have 9:15 michael o'keefe on it he wouldn't talk to me actually until i had published something 9:20 so in 94 my idea was let's link building units together with metal ions to make 9:27 extended structures and in fact we made the first porous metal sulfides this is you're looking at 9:34 it that was done at asu and i was very happy with this with this 9:40 development but i went to visit michael o'keefe in his office 9:47 to brag about my new result okay and [Music] 9:52 and i just want to talk about the inspirational power of molecular models if you knew mike o'keefe and you visited 9:58 his office you will see that it's completely decorated with different models because i think you can't actually study a 10:05 structure without building a model of it and so mike said 10:11 i i was wondering what that model looks like so this model ended up in my lab but really 10:18 started in michael o'keefe's lab and it's a structure that is known in 10:24 minerals but mike had figured out that instead of let's say a silicon 10:30 you could have a cluster of atoms and these cluster of atoms could be anywhere from the periodic table as long as they 10:36 maintain that geometry potentially this could be made and so he 10:42 actually said this when i saw this model i said what is this model he explained it to me it was my very first time to 10:48 see an extended structure quite honestly and and he explained it to me and 10:55 and then he followed that by saying i bet you can't make that and that's not a testament necessarily 11:01 that that i was not a very good professor or scientist but i think more that this was 11:06 really a more of a blue sky research and it's not a very possible 11:12 objective for a synthetic chemist and i said no i bet you that i can make 11:17 it and i took the model with me and gave it to haley and lee as you see 11:23 him here my my student well it turns out that we made 11:29 actually the even larger member of what michael o'keefe had 11:36 imagined and that's shown here this is a crystal structure of sodalite where the vertices instead 11:43 of having one tetrahedron they have 10 tetrahedra you see them here in 11:49 10 tetrahedra that have an overall tetrahedral geometry and you can put them on a 11:54 vertices of this mineral and actually make a porous in this case metal sulfide 12:01 well this was a whole new field of research right here okay we published in science in 99 and 12:08 you can see here mike o'keefe was a major contributor to this 12:13 in fact this is michael o'keefe's drawings on one of his uh now very old-fashioned 12:20 program but nevertheless very beautiful program and he put the yellow ball in there which has become famous 12:26 since then it started out as a pink ball purple ball red ball 12:31 where there was a lot of debate green ball and then in the end i made the decisive decision that the 12:37 yellow ball should be uh yellow because the the ball should be yellow because that was arizona state 12:43 university's logo on the on the logo i think it's still on the logo but in the meantime the 12:50 the this is the power of having models and discussing with colleagues who are interested in 12:56 discussion and in the meantime my students were 13:02 busy doing stuff and you know i'm a young assistant professor when i joined asu i was only 26 years old and betty 13:09 here in the front knows everybody's age and she can tell you for sure but i was 13:14 i was 26 years old and my students were making these kinds of compounds where instead of a metal 13:20 cluster an inorganic metal cluster they were linking organic units 13:26 such as these by pyridine neutral organic ligands this is the fact that it's neutral becomes 13:31 important later linking them with copper one and i looked at this and i said 13:38 oh gosh this is this is like the other hundreds of compounds that are out there in the 13:44 literature why are you doing this research and this student kept pushing this 13:50 actually in front of me this and other compounds she kept pushing those in front of me showing me 13:56 x-ray powder diffractions of them showing me single crystal structure and i kept saying i don't want to talk to you 14:03 i am i want to get tenure for god's sake i want to focus on the metal sulfides we've already 14:08 we've already been very successful with the metal sulfides not these metal organics the reason i was discouraged by 14:15 the student's result or approach was that these metal organics made from very 14:20 similar neutral linkers with copper one were reported back in 1959 14:27 and people have been making them since 1959. so 14:33 i wasn't and they were just in my opinion they were sculptures they were not useful for anything once you got the 14:39 crystal structure you drew it you admired it and that was it they didn't inspire new applications or use 14:46 as you will see because they collapse once you start using the pores you they 14:52 collapse and this is another example just to show in 1986 same thing neutral linkers 14:59 linked by copper and in 1989 robson reported same 15:05 kind of linkers neutral linkers with copper one made in exactly the same way 15:10 to make diamond nets in the same way 15:16 no different same reaction same metal same kind of linker 15:21 and same underlying topology but i want to pause here and say that many in the community 15:28 like to think that robson started the field of of reticular chemistry or mops 15:33 and as you will see you can judge for yourself okay by the end of my talk because what we 15:40 what i did having colleagues like peter williams and michael o'keefe and 15:48 all these ambitious guys peter busek and so on i have to get tenure and i have to do 15:55 something that makes a difference and so to me these were useless because i couldn't 16:00 make them truly porous they collapsed upon trying to 16:05 use the pores and and and so in the community this community was called crystal engineering in fact in the us 16:12 you couldn't get a grant funded in this topic because it was really 16:18 criticized by the establishment that this is not a viable field so 16:25 so what we did my training was in inorganic chemistry and so i knew that if you use 16:31 anionic links such as these carboxylates and link them to metal ions 16:37 if you could crystallize what we then called moths then you would then you would have 16:43 strong bonds you would have strong architectures and therefore you could potentially 16:49 exploit the porosity again i would like to point out that 16:54 those same group here robson's group 16:59 in some of their papers i discovered years later had written that in fact carboxylate 17:06 frameworks such as the ones we discovered in 95 would be impossible to crystallize 17:12 unfortunately they didn't have the nice students that i had in 95 at asu 17:18 and so we were off to the races we reported that in nature 17:24 and everybody was excited we were off in the direction of inorganic frameworks and 17:30 these moths so these structures that i showed you from previous to moths they collapsed 17:38 they were not designable this becomes very important particular chemistry is that they are made from vertices that 17:44 are single metal virtues not aggregates the carboxylates aggregated the metals so now you have clusters that can direct 17:50 the structure for you and make a stable structure they're not chemically stable and there are definitely not polymers 17:57 they're actually misnomer so those coordination polymers containing neutral linkers are not 18:03 viable for the things that i'm going to talk to you about so so immediately then in 98 we had to show 18:10 that in fact you can make a moth not just crystalline but that the pores can remain open in 18:17 the absence of guests and we use the strategy of carboxylates with metals to make these aggregates and 18:23 link them up into extended structures such as what you see here 18:30 and i had a student a postdoc come to me his name is muhammad adi while i was at 18:36 asu this structure was made by halyan lee and then muhammad adi as a postdoc came 18:42 to me and i said to him your job is to take this structure and see whether it's architecture robust by measuring the gas 18:49 adsorption isotherm which is done at 77 kelvin and it is the really the gold standard for proving 18:57 that your material can remain open in the absence of guests and therefore you could use 19:02 the pores this was this is the aspect that was missing in the field i actually have the referee reports on 19:09 this paper that basically said that 19:15 so this sbu approach was so amazing and later mike o'keefe and i started thinking about the carboxylate carbon 19:21 atoms as squares as forming a square so that now you have a square grid 19:27 so and the way we made them was quite simple you take the organic acid you link it up 19:33 with zinc plus and this is this is the key development here is that you have a way to 19:39 crystallize it under these conditions i won't go through all the details of balancing the kinetics and 19:44 thermodynamics of crystallization here that led us to single crystals but muhammad adi's job as soon as he 19:51 appeared in my office i said to him that your job is to measure the gas option isotherm 19:59 and he went to the lab and said which was in the basement of goldwater building here 20:04 he said you don't have a machine that measures gas absorption isotherms and i said well build one 20:11 okay so he went to the lab of wagner i think you remember dave 20:18 wagner had nanobalances that he used to use for catalysis to dose oxygen into his catalyst and 20:25 measure how much oxygen using a nanobalance so he interfaced the nanobalance with the um 20:32 schlenk line type device and really measure the isotherm 20:38 this is the very first isotherm that showed to the entire community that metal organics could be made 20:45 to be porous and uh and that's it this basically gave the 20:52 this field that was full of arc full of what i would say sculptures gave it um 20:58 [Music] a basis to go on and make frameworks that are now useful because now you can 21:05 remove the gas and put new ones in the new ones could be hydrogen methane whatever or you could functionalize the 21:12 pores and do very specific transformations so this meant everything but 21:18 there will always be people who say i've done it first but then when you look in detail they haven't done it 21:24 they just have done some experiment looks like the right experiment but it's not and and this is 21:31 one of them somebody took this compound and pressurized it with gas 21:38 at room temperature that's not a gas absorption isothermal you can pressurize any object even my tie and it will take 21:45 up gas okay so that doesn't prove porosity permanent porosity that doesn't mean 21:51 that i can evacuate on the molecular level the material and put new ones in so but this remains until today 21:59 people say not people but these authors saying that they prove porosity that doesn't prove porosity 22:04 especially since from this data you cannot get the porosity data which is surface area and poor volume 22:11 you can't use this data to do that you need the gas adsorption isotherm and 22:17 this is the measurement that everyone now uses this here 22:22 in the moff field every moth that is being used today is based on 22:28 metal carboxylates and it's characterized by 22:33 gas absorption isotherm in the way i see it here okay so 22:40 mike o'keefe used to sometimes pass by my office in the basement of 22:45 goldwater on his way to his office which was in the physical sciences building and this particular morning i had 22:52 forwarded him a crystal structure of a new compound we discovered 22:58 okay and that compound in response and i said what did you think of the structure and 23:03 he said this is so beautiful it will be the best thing you've ever done 23:10 and little did he realize that we will do much more than that together and that's really the magic of 23:16 that collaboration that compound was what we called map okay 23:22 so mark 5 was discovered in my lab at halian's initiative of linking metal 23:30 oxide units with organic linkers or doing the reactions that would produce these metal oxide units and this was 23:36 really the beginning of the the true beginning in the eyes of the public of 23:42 of um or the community of of the maf field because the surface area when we measured the gas absorption isotherm was 23:50 so high that people when we published this paper people thought it was a misprint 23:57 surface area is 2 900 meters square per gram in the basement of goldwater when the 24:03 students they had not slept for a whole night muhammad and halian measuring this 24:10 point by point because you have to wait until each each dosing of the gas has equilibrated and 24:17 the and you have a constant uptake measurement and so it took them all night 24:23 and i said is it reproducible and of course they thought oh gosh not another night 24:29 okay they keep reminding me of that until today so we made sure it's reproducible 24:35 and on top of that i wasn't going to say to the world i just broke the 1000 year 24:40 record held for porosity by carbon without sending it let's say to an independent 24:48 company at the time in georgia to confirm that the surface area was 24:53 what we think it is actually the numbers always hovered above 2 900 25:00 because we didn't in those days we didn't quite understand the chemistry of the poor we can evacuate the poor but we 25:07 could never figure out is it completely evacuated or not it turns out that maf5 now we can 25:14 activate it so well that it has a surface area of almost 4 200 meter square per gram 25:20 but we went and reported the lowest number that we obtained just 25:25 because as an assistant professor i was worried that i might make a mistake 25:31 so anyway it turns out to be higher than that and now we have the concept of sbus 25:38 articulated by mike o'keefe and myself in that now you take the carboxylate 25:43 carbons to have a primitive cubic structure and once you know the conditions under which to make this 25:50 you could functionalize the linkers and make the same structure what we called in those days iso reticular 25:57 structure meaning having the same underlying net well 26:03 it didn't take mike very long to recognize that basically any building 26:08 unit that you could get your hands on which could be a geometric unit can be 26:14 linked together into into a network that he had described in his book 26:20 the yellow book that was already published when i joined asu 26:26 so we could take linkers that are benign such as acetic acid or 26:33 terethalate lactic acid and make moths out of them so you can make muffs that are edible 26:41 let's see they've been eaten by some of started students and 26:47 and you can make moths from the most exotic linkers so 26:53 so what what this meant is that any linker any cluster that you can imagine 26:59 you can get your hands on you can make it into a move remember these mobs are structures that 27:05 people said they could not be crystallized and so you can imagine the excitement in the field 27:12 so like i said with mike's thinking about using the building units of geometric objects 27:18 we were able to then these are mike's drawings actually 27:24 we were able to take squares when with the proper organic linker that can put these 27:30 squares at a required angles we could make zero-dimensional structures chains ladders square grids 27:37 and three-dimensional structures so so all of a sudden a linker like 27:43 terethalate became conveyor of geometric information so 27:48 that you can make them off that you desire the the the um 27:53 terethali depending on the angles between the carboxylates whether it's the bending angle the twisting angle or 27:59 the folding angle they were all now important information that can channel 28:04 you into the desired structure and needless to say we were able to make all 28:11 of those we made the this is the bend structure puts the squares at 120 28:16 degrees together and make the first nano 28:21 particle that has been characterized by single crystal x-ray diffraction okay so this is a truncated cube 28:27 octahedron and i won't go through these but you can see that 28:32 we went through the [Music] um [Music] through the exercise of making sure we 28:38 find or we designed the right uh linkers that provide you with the angles 28:45 required to make those moths and in those topologies this is a this is a scenario a very nice 28:51 scenario where here in this example you have 28:58 the squares could be so the squares here are in the same 29:03 plane so you make the square grid and if you have one bromo one halogen 29:08 here that puts the carboxylase at 90 degrees and if you don't heat this moth structure 29:15 you'll be able to keep the carboxylase at 90 degrees they won't overcome the barrier to rotation and now you have a 29:21 three-dimensional framework okay so we showed the feasibility of making 29:27 moths in crystalline form we showed that you can take the interior of the maf out and use 29:33 the space inside okay this uh then was a an emerging new field 29:41 because anything a chemist can imagine now we've shown that you can make 29:46 so it was time to sit down and put a really a thinking basis for 29:53 the field in terms of which geometric unit could give you which structures and of course you can imagine there is infinite number 30:00 of structures that could be made in this way depending on the geometry so so mike came up with this idea that all 30:07 structures can be viewed as collection of linkers and intersections that allowed us to basically take any 30:14 structure no matter how complex it is and reduce it into two components one is the node that's your branching 30:21 intersection and the other one is link and depending on how these things came together you 30:26 made a net and that net mike o'keefe 30:32 who was called by many the net guru was able to identify it or predict it 30:37 and so so that's this is done in his book 30:42 first this idea of making nets from nodes and links was introduced by 30:48 af wells and and really perfected and applied by michael o'keefe in his uh in his book 30:56 so and we built a website that basically tells you which structure you're going to make by combining which 31:03 geometries together that's the reticular chemistry structure resource 31:09 so how do you choose from among the millions and millions of possible structure almost infinite number of 31:15 possible structures and mike 31:20 said for the assembly of symmetric molecular shapes only a small number of simple high symmetry structures will be 31:26 of overriding importance and they will be expected to form most commonly okay so you're as long as 31:33 you're starting with symmetric units you're probably going to fall very likely fall in the more symmetric nets so that made life 31:39 much easier for for mike to basically say hey if 31:45 if i want to know what the synthesis is going to produce i have to go after the most symmetric structures 31:51 and those turn out to be not many it could be you know 50 or so for different geometries and 31:59 most of the time he was correct sometimes he was not correct we made 32:04 things that were not as symmetric as he thought but most of the time it was correct it it it became an intellectual 32:11 framework to putting building units together thanks to mike's work 32:17 and we came up with what i call the periodic table of reticular chemistry so if you're a student and you can think up 32:25 building units all you have to do is come to this table and say okay i've got triangles and this is what they're going 32:30 to give me different geometries and these were 32:35 enumerated by mike for many different geometries 32:41 progressively higher connectivity and higher complexity and you can see here 32:47 for those in the audience who are interested in this field there's still plenty of room for you to contribute 32:53 by making some of these which have not been made yet okay 32:59 so the field started in 95 by the crystallization of the first moth 33:04 they were named moth at asu in that paper and 33:10 in 99 because of the ultra high porosity that broke all records of porosity that 33:15 paper with mike on that paper became mafs became a sensation and now 33:23 in 2020 the research is being done on moths in over 100 33:29 countries around the world so they've given a lot of inspiration to emerging scholars to young people who 33:35 want to enter chemistry but also they are very seriously being researched 33:41 by groups either on making moths studying moths 33:47 or applying moths in various um uh applications 33:53 okay so that was metal organic and i was always i was always i was always excited by new 33:59 frontiers how do i build the next new frontier moths 34:05 we were doing mops and we are still doing more of chemistry but i wanted my excitement came 34:10 from building the new frontier and that we have always i've always been interested in linking organic compounds 34:17 together to make extended structures and roald hoffmann back in 93 although i didn't discover 34:23 this statement until much later i wish i did i would have put it in my proposals 34:30 but he said that there is nothing nothing in two and three dimension there's no 34:35 infinite extended organic structures that are covalently linked in two and three dimension so it was wide open 34:42 nobody has managed to crystallize anything for uh organic compounds in two and three 34:49 dimension because every time you did that you got a powder diffraction that looks like this 34:54 and a chemist can't do very much with that okay it's it's very poorly crystalline 35:00 or amorphous so what we did in my group we were able to turn this into a true 35:06 crystalline material and that's from this reaction taking this diboronic 35:14 acid and dehydrating it you would think this is a simple reaction which it is 35:20 but it doesn't make crystalline material so it took the students many years to get this to work and these 35:27 are the magic conditions where water is produced in this reaction and because you're running this in a sealed tube you 35:34 can control the pressure of water to control the reversibility of the reaction therefore 35:39 the crystallization of the cough i can i can talk for an entire lecture 35:45 about the discovery of coughs because it is a true expression of the importance of 35:51 the interaction between the professor and the student in a pleasant way so 35:57 that's that's that hump that i showed you turns into very sharp x-ray potter diffraction 36:06 that was cough one the very first cough we published in 2005 and this is the structure that we obtained from 36:12 x-ray powder diffraction three-dimensional structures could be made by make by starting out with 36:18 three-dimensional uh four connected tetrahedra let's say 36:24 building units and dehydrating that to make triangles as links 36:30 and the the organic links that you put in the nice thing about coughs is that 36:35 unlike moths what you put in does not change they're only linked together through one bond 36:42 or one form they don't really decompose and come together again so 36:48 they're very predictable and because mike had worked out which nets we're going to produce from 36:54 which building units it was easy for us to link them together and then look at the powder diffraction and match it to 37:01 the simulated positive fraction that we got from the predicted structures 37:08 that's why you see mike's name on some of these cough papers these are the nets that mike had 37:16 predicted for joining triangles with tetrahedra these 37:21 are the two most symmetric possibilities and both of them we made by matching the simulated x-ray positive 37:28 fraction to the experimental positive fraction that gave that gave us the initial model to to 37:34 to refine the structure this turns out to be one of the least dense materials known today it's 37:41 entirely composed of boron oxygen and carbon linked by covalent bonds 37:48 well that field now just recently we were able to make 37:54 something that mike said that that he would retire if i could link molecules by 38:00 carbon-carbon bonds okay he said something more severe than that 38:06 but but anyway so so we did 38:11 and the conditions that we use for the initial coughs were modified but now adding trifluoroacetic has a 38:18 very strong acid to reverse the reaction but still lock it down into this incredibly stable structure this is a 38:25 carbon-carbon bonded linker and of course carbon nitrogen these are all very strong bonds 38:32 this is an amazing structure no one would have predicted that you can do this under 150 degrees under such mild 38:40 conditions or or at all actually because if you go to a very high temperature you're going to decompose your call 38:47 so this is the x-ray positive fraction and you can see that 38:52 we use spectroscopy nmr and ir to make sure that the right linkages are being made but look at the stability you can 39:00 take this cough and put it in concentrated hcl saturated koh 39:06 in in water in methanol do whatever you want put it in corrosive and butyl lithium and the structure is unaffected 39:13 and that's what we expected with carbon-carbon bonded frameworks okay 39:20 that was that's the holy grail of coughs so now the rest 39:25 is just a lot of trials and errors to find the right conditions for other carbon-carbon 39:31 bonded structures but the path is already open and i don't want to 39:37 just say that we solve those crystal structures by powder but we also more recently 39:43 have been successful in making single crystal structures or single crystals of these coughs large 39:50 single crystals okay and you can see here the size is the same 39:56 size that an organic chemist would have for their molecules but this is an extended infinite structure avogadro's 40:03 worth of unit cells that are linked together entirely by covalent 40:09 by covalent bonds so and thus the birth of what we call 40:15 reticular chemistry so in 2003 mike and i wrote a 40:20 i would say a foundational paper that defined the parameters of the field and the definition of reticular 40:27 chemistry has three components i don't know how you can actually 40:32 see the future and write something of this kind that is still valid until 40:38 today it's just building blocks strong bonds to make durable materials 40:43 building blocks to design structures strong bonds to make durable materials that are going to harvest water from air 40:50 year after year after year and crystalline so that you can define 40:55 your structure on the atomic and molecular level and know the and understand the chemistry of that 41:01 framework so this is still valid until today and i don't think anybody can modify it any 41:07 better to make it fit what is happening today in the field so that resulted in moths 41:13 and coughs and more recently molecular weaving this is another extremely exciting field 41:19 we discovered we were the first to discover molecular weaving and when i sent our paper to 41:26 michael o'keefe he was busy predicting the next generation of 41:33 molecular woven structures and i think he calls it now decousade chemistry the chemistry of crossings i 41:40 this is really i'm not doing justice to the molecular weaving because it has it does propel 41:46 moth chemistry into the making materials that have incredible mechanical 41:53 strength and and but this is a topic for another 41:58 another so i'd like to to put now in context of the 42:05 larger chemistry and society what we have done 42:10 together we have made new materials and new materials in general have tracked 42:16 very closely with advances in human civilization in fact we humans refer to those as different 42:22 ages like stone age to define the materials that we were using at the time bronze age and iron age and glass age 42:31 steel age and aluminum age and the plastic age and the 42:38 the more we are able to design these and manipulate them on a finer and finer level 42:44 the better our lives got okay so we have the molecular age i would say in 42:50 the last century that led us to pharmaceuticals mainly 42:56 pharmaceuticals and then i would say we are and this is not ostentatious this is can be 43:02 supported by evidence the reticular age okay 43:08 reticular age because it controls matter beyond the molecule into infinite 2d and 43:14 3d that's that's the materials world but it's it's well defined on the atomic and 43:19 molecular level and you can use molecular chemistry on the extended systems so who could argue that 43:27 this is not the reticular age okay so 43:33 so we were awarded the amino prize which is a very nice prize 43:38 that is it's it states that those people who get it have done something beautiful 43:44 [Music] and useful and i think i think that 43:49 mike o'keefe's statement when we discovered ma five it is so beautiful and that is really true 43:57 and there's nothing like it so for this is for the development of particular chemistry i'm i'm especially honored 44:04 to have received this prize with michael o'keefe okay so now 44:10 very quickly in the time remaining i want to just give you an idea of what some of the things that we have been doing 44:17 with mafs in terms of applications i think that there are three stresses facing our planet 44:23 one of them is the stress of trying to use clean fuels like hydrogen which burns with only 44:30 water as a by-product that's a dream that that potentially we can address or 44:36 that's a challenge that we can address carbon dioxide 44:42 a child born today breathes almost double the amount of carbon dioxide than one that was born 44:48 before the industrial revolution and that tells you the extent of the problem and it's getting worse and it's affecting our climate 44:55 and water right we'll talk more about water in fact i want to zip through hydrogen carbon 45:00 dioxide with a couple of slides and then focus on water but fortunately 45:06 we have the periodic table and with reticular chemistry we have a way to stitch these elements together to 45:13 make new materials that i believe are beginning to address this these 45:18 challenges materials are going to become more and more complex i think 45:23 and that's why reticular chemistry is so attractive to students to young scholars 45:29 because it's all about control it's all about the control on the atomic and molecular level once you're able to 45:35 control matter on that tiny level you can solve any problem 45:42 as long as society has the will to put the resources behind it but i don't think 45:48 we have failed in solving problems once we have that control 45:53 and the resources to express it and here's an example of 45:58 i just like to give this example our cell phone has more elements in it than 46:04 than our human than the body human body okay and that just tells you we need to 46:10 be able to control things more and more so that we can make uh objects that are able to carry out 46:17 complexity and that are durable and robust that's reticular chemistry that's a 46:24 strong bond okay so one of the things that we have done is hydrogen storage this is a moth 46:30 in red and the white spots are the hydrogen molecules 46:37 and the idea is that instead of hydrogen filling a very large volume 46:43 we create a maf that could attract the hydrogen through electrostatic forces or polarization forces and therefore you 46:49 can pack it on its internal surface and therefore stack the hydrogen molecules 46:55 like you would let's say stack cars in a in a car park and here 47:01 you see how the hydrogen molecules are hovering in this 47:08 computation hovering around the maf structure and therefore you're able to store more hydrogen 47:15 per unit volume with the moth than without them off even though the maf occupies its own volume 47:21 you still can store more within them off than without them off except that 47:27 you have open space here that's not doing you any good right that's that's open space so 47:33 your your fuel tank is going to be so much larger 47:38 because you have this open space but reticular chemistry can fix this because we know how to design 47:44 materials that could self-caterinate again enumerated by 47:50 michael o'keefe and that's that's this structure you could fill that space by having two 47:56 independent frameworks come together and mechanically fill each other 48:02 that way now i have introduced more absorptive sites i doubled my adsorptive sites per unit volume 48:10 and so this is the results of that experiment where this is now at room temperature we're taking up hydrogen 48:18 over 1.5 by weight not a lot but significant 48:24 and it's reversible because not tied to the framework by covalent bonds so let me just uh make a long story 48:31 short here because this is an ongoing research we are right now with hydrogen 48:37 in terms of binding energy the strength of interaction between hydrogen and the framework we are at about 12 to 13 48:44 kilojoules per mole and that gets you around two percent by weight 48:50 okay not in this structure but another structure that has an exposed metal side so two to two point five if you really 48:57 use the right metal but 2.5 is the absolute maximum of where we are right now 49:02 at this binding energy this is for mop five so we have been able through tinkering 49:09 with the moth to get it to be stronger and store around two to two point five 49:14 weight percent of hydrogen we need to get to 20 kilojoules per mole to be able 49:19 to store enough to make it interesting for automobile fueling 49:24 so 20 kilojoules per mole that's the strength of a hydrogen bond 49:30 okay but you can't go stronger because then you have to put in heat to take it out 49:35 you can go weaker because then you can't store enough hydrogen so that's you know for those of you who are interested in 49:41 this problem we need to think of strategies of how to functionalize the interior of the moth 49:47 to increase the binding energy of hydrogen to the maf 49:52 to be to go from 13 kilojoules per mole to 20 kilojoules per mole do you think could be done or if anybody's going to 49:59 do it it's going to be in the moth field because we can control these on the molecular level okay that's that i think that that's the 50:05 key development here on a foundational at the at the fundamental is that we can 50:12 control matter in infinite direction on the atomic and molecular level 50:19 uh co2 problem is potentially more it's complex problems to solve but 50:26 it gives me even more hope that hydrogen the problem is you could divide it into two 50:32 two sides one is binding co2 from air where it exists at 50:40 around 400 ppm that's not so easy because very dilute so you have to 50:46 process a lot of air and that has its own energetic and 50:51 engineering challenges and from power plants and point sources depending on 50:56 what your power plant is burning it could be five percent co2 emission if it's burning natural gas 51:03 but if it's burning uh petroleum or or coal you you could get up to 16 of co2 51:12 in both cases you're trying to separate co2 from many other gases not the least of which is water 51:18 which competes with co2 and so and complicates things 51:23 so these are the minimum requirements for a carbon capture material you need to have 51:29 high capacity so that you're not doing many cycles you minimize the number of cycles by having 51:34 a high capacity material because every cycle demands energy water stability your material needs to be able 51:42 to be flooded in water and stable for many years in a power plant or in a device that's capturing co2 from 51:49 air oxidation stability because you you have oxygen around 51:54 and you're heating the material to remove the co2 um that the oxidation of amines and the 52:01 oxidation of the framework is very important site callability you need to be able to cycle 52:07 many many times hundreds of thousands of cycles and you need to be able to have the right 52:13 regeneration temperature you need to be able to heat your material not to hundreds of degrees 52:20 celsius but but to something that is more reasonable to lower the energy requirements 52:27 so where are we in the carbon capture world okay we are we're here there isn't 52:35 an ideal material right now they all have problems they they all have problems the aqueous 52:41 amines which have been used for 100 years to separate co2 from 52:48 methane in natural gas mining is are problematic because the regeneration temperature is high 120 degrees 52:55 they're not very recyclable can't cycle too much because they decompose and they become problems in 53:01 their own uh environmental problems and and amines are corrosive 53:06 they're liquids they're water they're they are aqueous amines and 53:12 and the heat capacity of water is high so frameworks may be better or solid better 53:19 because they have lower heat capacity carbon doesn't cut it zeolites have their own problems resins organic resins 53:27 are not bad but they do have a problem with regeneration temperature silicas 53:33 as you can see here they still have problems metal hydroxides have a they're solids they're 53:39 they have problems with high regeneration temperature maf seemed to be approaching being interesting 53:46 right as materials that could satisfy the three requirements cyclability for maf is still a challenge because after 53:53 many many cycles somehow having the metal there still affects the hydrolytic stability of the 54:00 material but that's where let me just say that's where coughs are going to fill in but we're learning 54:07 a lot about co2 capture even though moths may not may not be 54:12 the ideal materials down the road and there may be smaller applications that can withstand 54:18 lower number of cycles that moths could be useful for but but for power plant 54:23 and this large scale applications you're going to have to go with materials that are not going to hydrolyze because remember even when co2 54:30 unlike binding h2 into the pore co2 is going into the pore with water 54:37 binding to a means that you may have tethered onto the moth and and evolving its own chemistry 54:44 okay you make acids and it's constantly evolving within the pores as more and more co2 is being 54:50 pushed into the pore so it's very you have a almost like a chemical plant into the maw 54:57 and so the material has has to have a backbone that is extremely robust 55:03 onto which you can bind amines and the things that you need for the co2 selective capture 55:10 at the level where we are with moths here's a maf it's a zirconium moth and we functionalized it with a 55:16 with glycine which has a ch2 and h2 unit onto which co2 could bind from air 55:23 okay and how does this material perform in air here's 400 55:29 ppm we can reduce this is one kilogram of maf we can reduce that down to 55:36 as you can see here down to 0.02 millibar or 20 ppm so that's that's not bad you 55:44 have a material that can take this up and we can cycle it over 80 cycles 55:49 and it's fine i'm not sure how many cycles we can do 55:54 but i'm worried the flue gas is the same thing 15 co2 we can clean it down to less than percent 56:01 co2 so you see right before you a prototype 56:06 that has a maf that can selectively bind co2 and reduce the level of co2 in air or in 56:14 flue gas and it works in water and it can be cycled quite a few cycles now will it cycle 56:21 hundreds of thousands of cycles i don't know my guess is that it's going to be complicated that's why 56:27 the push should be towards coughs okay the other 56:33 problem i want to talk about is the problem of water stress in the world and 56:39 all the regions that are not yellow are experiencing water stress in one way or another 56:44 either for the lack of brain or because they're over using the underground water 56:50 so that's one third of the world as of today lives in water stress regions and 56:57 even in the water regions there's always questions about how pure is my water 57:02 and then it's also a national security problem for many countries because many of them 57:08 do import their water okay so you don't want to rely on another country for your water 57:13 um so in 2040 the un projects that this 57:18 picture will get even worse countries that you think are not water stressed or regions of countries where you think are 57:24 not more stressed like the midwest of the u.s or the east coast will be water stressed because we're overusing the 57:30 underground water much faster than it could be it could be replenished 57:36 so our idea is that the air contains a lot of water 57:42 and in fact we have almost 13 000 cubic meter kilometers of water 57:49 in air at any one time that's as much water as we have in lakes and rivers on 57:55 our planet it's a lot of water but we don't have a way to extract that 58:00 water in an energy efficient way now moths come in because you can design 58:06 the interior to have the right binding energy for water and so we think that 58:13 potentially this is something that we can address in fact water harvesting is probably the 58:19 furthest along among the hydrogen co2 problems 58:24 now there's a lot of stuff out there on harvesting water from air because this is an idea that has been around for a 58:30 thousand years okay and if you google water harvesting you'll get all these 58:36 things that people will trying to sell you as harvesting water from air and none of them work 58:43 they all work at high humidity not at the humidity levels where you really need them to work which is less than 50. 58:50 in the desert usually 20 to 30 relative humidity okay depending on the 58:56 uh time of year so these all these systems work on cooling the air down 59:03 to get the water out okay we're going to do something different 59:09 we think that if we can have a moth that extract water from desert air at low 59:14 humidity it would work anywhere in the world it will work better at higher humidity 59:21 so that's the idea that's the vision could we harvest water from air anywhere in the world at any time of the year 59:29 and to make you appreciate and so that you don't buy those equipment online 59:35 to thinking that you're going to get pure water in the middle of the desert i just want to give you an illustration 59:41 this is a psychometric chart plotting the amount of water in air versus temperature 59:46 okay if if i am in a region of the world that is here 30 where this 30 degrees c 59:55 and 20 relative humidity that's very dry okay 1:00:00 not much water is in the is in that air now for me to to get the water out of 1:00:05 that air i need to reduce the temperature down to four degrees celsius of the air 1:00:11 and dave is nodding his head because an engineer understands that very well that's energy intensive process you 1:00:17 can't make devices that you're going to sell to people and and address the water stress 1:00:24 however if i have a mop that can seek out that water pluck it out of the air concentrate it into the pore 1:00:31 now i've created humidity in my environment and i have 80 percent humidity and so for me to get that water 1:00:37 out i only need to reduce down the temperature or for me to condense that water 1:00:42 would would require me to reduce the temperature by four degrees to get the water out of that air 1:00:48 okay so in a way the moth being able to concentrate the water from air into its 1:00:53 pores creates let's say humidity in a device 1:00:59 so that you have a humid so that you take let's say arid air desert air and turn it into a 1:01:05 tropical air okay now you can get the water out much more easily that's how the moth works 1:01:11 and and i don't want to belabor the point but there's again there's a lot of fluff 1:01:16 out there about water harvesting and a lot of claims that when you look deeply into what 1:01:21 they're claiming it's not quite right okay you need to have a high capacity 1:01:28 material you need a material that can take the water in and out with great facility so that you're not putting in a 1:01:34 lot of heat to to do that and you need the material to work at low humidity otherwise we already have water 1:01:40 in in the more humidified region or it's not as urgent so there's nothing out there that works and 1:01:47 what works here is moth with the way we discovered this is that 1:01:52 we were studying the interaction of water two mobs as part of the co2 capture problem 1:01:59 and we discovered this moth to have this incredible behavior when exposed to 1:02:05 water it takes up water 20 relative humidity and it takes it up in a step 1:02:12 way and so that means for me to take the water out i can i can have a very high working 1:02:18 capacity because of the step if this was shallow your working capacity would be very low and would require more energy 1:02:26 so we discovered that you can take the water out at 45 degrees which is having 1:02:31 been born and raised in a desert environment that's the temperature during the day could go up to 45 degrees 1:02:36 so that gave me the idea that moss could be used for harvesting water from desert air 1:02:41 and indeed you can do this for many many cycles and the maf is maintained maf structures 1:02:48 many other performances maintained the only thing that we notice is that there is a slight drop in performance or an 1:02:54 uptake after the first cycle what was that and now comes why are we working so hard 1:03:01 to make crystalline materials is that it does have aside from the obsession of mike o'keefe and omar 1:03:08 yagi with crystals there is a practical thing and that is now we can dig into the structure and 1:03:14 find out where those first water molecules are residing and what's their interaction with the 1:03:19 framework it turns out the very first water molecules are bound closely to the metal oxide unit 1:03:28 and so when you're doing the cycling these i call them seeds are not removed they 1:03:33 are stuck to the metal oxide unit through strong hydrogen bonds but what you're removing are the water 1:03:39 molecules that are bound to the seed so in a way you have a an ice fragment growing inside the mouth at room 1:03:46 temperature and that's what we were cycling we were cycling the additional water molecules that are 1:03:52 bound to those to those seeds well that's great right now we have 1:03:59 figured it out and we can do better right but before that we wanted to show 1:04:05 that this thing works in the desert okay so we designed a uh 1:04:12 in collaboration with evelyn wang at mit we designed a handheld device that 1:04:17 employs two grams of water and the device works by you open the 1:04:22 device during the night for air to get into the moth water gets into the mouth you close it 1:04:28 during the day expose it to sunlight it heats up and water comes out of them off 1:04:34 and condenses on the walls and that's and you can see here the droplets of water as the interior heats up 50 60 1:04:40 degrees and so on you get the droplets are getting larger and larger okay so not much water is 1:04:47 coming out but we are only using two grams but it works it works outside the lab 1:04:54 in in this particular case this was done in in a humidity of 25 to 30 relative 1:05:00 humidity this is this experiment was done in arizona in the arizona desert and you 1:05:06 can see the droplets that were harvested from that device 1:05:12 so evelyn and i went our own way because mit gave her a whole bunch of money and said yagi can't work with you because 1:05:18 he's not an mit professor so so i said fine i mean 1:05:23 we can design a device a simple device to do this no no problem okay so 1:05:29 a berkeley device has is based on a kilogram of moth and it's a box within a 1:05:34 box okay that the outside box is your condenser the inside box has the moth it 1:05:40 works in exactly the same way desert air comes into the moth traps the water the water the moth gets saturated you close 1:05:48 the outside you expose it to sunlight and you get condensation of water as the water is moving out of the moth 1:05:54 okay from this experiment which by the way this is 1:06:00 i think this is betty's backyard right here that this box is sitting on so i called betty and i said betty we 1:06:06 need the students need to test this kilogram device in a desert environment could we borrow your backyard and betty 1:06:14 and and john were gracious to host the three students 1:06:19 and this is what the device looks like it's it's two plexiglas boxes that are you can see how asu is in my blood 1:06:26 okay so so ultimately the student i didn't tell you betty but i called them up at two 1:06:32 o'clock in the morning and they said oh the experiment is not working we see we see that the because they have probes 1:06:39 into them off and everything we see that the muff is getting saturated with water 1:06:44 but and we see it coming out as vapor but it doesn't condense 1:06:49 i said just put it under the ground put part of it under the ground and the dirt is probably two degrees three 1:06:56 degrees lower in temperature than the rest of the device it should condense and indeed then that worked right so it pays to 1:07:03 call your students at two o'clock in the morning so these are the three students who were 1:07:10 doing this experiment in betty's backyard you can see here the um 1:07:16 production is 200 milliliters to 300 milliliters that's a wrong that's a more 1:07:21 that's a a cup of water this is 236 milliliters so it's a drink of water from a kilogram 1:07:29 completely unoptimized and then we discovered that not all the moth is being used because air has to diffuse 1:07:35 further down into the cake of moff but now we've gotten a lot better as you will see in in exposing them off to um 1:07:43 all right ready yeah so this is eugene uh you met him betty 1:07:49 he drank the water without my advice 1:07:55 nice 1:08:00 the water is pure we tested the water for using the 1:08:06 fda standards for drinking water and it has no metals no organics it's it's it's distilled water okay so it 1:08:13 doesn't really taste as good as this water but to make it taste like this or even 1:08:18 better you mineralize the water all our water is mineralized it's very easy cheap 1:08:23 process so this is very very exciting because you have a material 1:08:30 a simple device you can generate water without any energy input aside from 1:08:35 ambient sunlight and we learned a lot by going to the desert and and 1:08:42 doing all those experiments and understanding all the heat transfer air flow and temperature changes that are 1:08:49 happening in the in in the device so that so then as we publish that paper 1:08:56 everybody said oh zirconium is too expensive and that's true and so we went and that's the nice thing 1:09:02 about reticular chemistry we went and designed aluminum moth aluminum is cheap 1:09:11 o'keefe had already enumerated rod-based sbus and this is one of them 1:09:17 mark 303 we designed that we we it turns out to have extraordinary 1:09:24 uh uptake and it works at ten percent relative humidity 1:09:29 and it works better than the zirconium off okay i'm i um i just want to say 1:09:34 that we took the a kilogram of that moth to the desert mojave desert 1:09:40 and you can see here the humidity in the desert at this time of the year when we tested 1:09:46 this and the uptake of water they ignore the first bar because that's the water that was in the moth when we 1:09:51 were in berkeley but this is in the in the desert and you can see that even at very low humidity 1:09:58 less than 10 percent of the humidity here or 10 percent really humidity it still picks up water 1:10:05 okay so and my students know not to return without the evidence of water real 1:10:11 evidence of water being picked up from air and so this is a video of 1:10:16 of the this is part of a longer video that shows how the water is dripping into the 1:10:21 container and from this experiment we can harvest one liter of water per 1:10:26 kilogram of moff per day at a humidity that range from 5 to 35 1:10:32 relatively humidity i said 10 percent but you see there's a very short 1:10:38 hump at the beginning that's five percent but largely the malforce at 10 but if you have 5 it does pick up some water 1:10:45 so the nice thing about this is that the mop stays in the device 1:10:52 for many years right because we've already tested this moth over 36 000 cycles and 1:10:59 it leaves the water leaves no imprint on the moth the moth 1:11:05 performance is reproducible and the very nice thing about this is that the water comes out of the pore with a great 1:11:11 facility at 85 degrees you can remove the water from the pores in less than 1:11:18 five minutes okay just a few minutes if you want if you don't want to go to 85 you can go to 60 but that means you 1:11:26 have to do more cycles or slower cycles excuse me based on that you can do an electrified 1:11:32 device like this looks complicated but it's not it's just made on the same principle 1:11:37 that i showed you before from which you can harvest uh 1:11:43 four liters of water but not kilogram of maf 200 1:11:48 grams of moff this is the water harvesting chamber door opens allows air in 1:11:53 it condenses it it's it's into the moth then the mouth is heated condenses it's collected at the bottom 1:12:00 and then you see the water filling up the the bottle there this is the water at the bottom 1:12:11 okay so let me let me just say that from this experiment 1:12:17 we you we are using 200 grams of maf in here only 200 grams and producing four 1:12:24 and depending on the weather five liters of water a day the water is ultra pure 1:12:29 because the maf is a filter molecular filter in itself and it does not 1:12:36 let's say leech any metals or organics and you can see that 1:12:42 because we can control matter on the atomic molecular level we can in not a very long time really achieve a 1:12:50 much higher productivity now we are looking at the prospect now we are here at around 80 liters per 1:12:57 kilo of maf per day we should be able to get to 100 liters per kilogram 1:13:03 of maf per day okay 1:13:08 well this is my one of my last i guess my last slide 1:13:13 if if like i said if the maf works it will work in any kind of weather because 1:13:18 if this one works at five percent mainly 10 relative humidity and so in the driest desert in the world at the driest 1:13:25 time of the year this material would pick up 1:13:31 about seven or so liters of water per day 1:13:37 for each kilogram of moth and you can do this in all parts of the world 1:13:44 okay because arid or humid whether the humidity here 1:13:50 and the temperature doesn't change based on where you are necessarily in terms of the behavior of the material 1:13:56 so that's that's where we are i think that we are realizing the um 1:14:03 the fact that you can harvest water from air anywhere at any time of the of the year 1:14:08 um the fact that these are highly crystalline allows us to incrementally 1:14:13 introduce water and then check where the water is residing inside the structure 1:14:19 and let me just zip through this and give you the video 1:14:24 so these are all based on crystallography this is one of the pores and we're going 1:14:31 to uncover the pores so that you can see where the water is going that's the 1:14:36 first absorptive size second third and fourth 1:14:42 okay and then it fills up that that's those are our seeds 1:14:48 and then it fills up now you're building an ice crystal in the pore 1:14:54 all of these positions are crystallographically uh defined 1:15:00 the reason this is exciting is that once like all chemists know do once you know 1:15:06 where what the site that you want to modify you can go in and make the binding stronger or weaker 1:15:13 okay and so we could use linker like this instead of the one with nitrogen to shift the isotherm if we 1:15:20 want towards taking water at higher humidity i don't know why you would do that if you have that maybe this is more 1:15:26 energetically favorable if indeed all your conditions are going to be around there but but more importantly 1:15:33 you can then modulate at which temperature you can take out the water 1:15:39 by crafting in which atoms are being bound to to water molecule 1:15:45 to the framework okay so this is the this is the end of my talk 1:15:51 before i get any questions about me taking water out of air and leaving us all dry 1:15:56 i just want to say that we if you serve 50 liters to each one in our population we would 1:16:02 have only used less than 0.001 percent or 2 percent of the water in the 1:16:08 atmosphere we have lots of water in the atmosphere on a fundamental level what we are doing 1:16:13 is we are making distributed water mobile of bread and of course you can personalize you can mineralize it you 1:16:19 can make it flavored if you like and it's pure pure drinking water you can you can 1:16:26 use it for household uses for agriculture and above all we can achieve hopefully water 1:16:32 independence by using this kind of methodology michael o'keefe has played a major role 1:16:38 i think in the development of beautiful structures so this is a symposium that we held for 1:16:45 beautiful structures for mike and defects for osamu who spend his lifetime working on 1:16:52 defects this this was held in vietnam part of our global science institute activities to bring in 1:16:59 people from developing countries into science and research and i just want to say that mike never 1:17:05 hesitated to jump on an airplane and go to very far places and spent a week to mentor 1:17:11 students or giving them lectures and i appreciate that very much he also um 1:17:18 has never hesitated to interact with my students in a productive way as you see here on one of the boats that they 1:17:24 surprised me for my 50th birthday with mike and there is lita keeping 1:17:30 everything in order and running smoothly thank you lita for your support 1:17:35 and asu is a very special place to me because i met some people who have really impacted my 1:17:42 life in the beginning and it had tremendous impact on my career one of them is 1:17:49 morton monk he's sitting there in the back who always said whatever you need omar i 1:17:55 will provide okay and i called upon him several times to help me and he did no hesitation it 1:18:01 takes courage to do that and it's it in the end it translates 1:18:06 into into big impact betty landon she made sure everything is in order 1:18:13 and everybody knows their age and not to exaggerate their age so thank you betty for all for your 1:18:20 friendship and all your service to our uh to our department okay 1:18:26 in the end i want to acknowledge my students in addition to those i acknowledge during my presentation 1:18:32 my our funding and partners and also say that 1:18:37 we have you have two textbooks that describe reticular chemistry one is based on structures and nets that's by 1:18:44 michael o'keefe and bruce hyde and the other one we just published in my group on an 1:18:50 introduction to reticular chemistry it's a textbook designed for undergraduates to follow the 1:18:58 synthesis structure properties and applications of of reticular chemistry and i'll end 1:19:04 with this statement from mike there has been nothing like it in the history of 1:19:10 chemistry moths coughs i think the interaction with 1:19:15 mike i think that it's uh it's been a a wonderful journey and we will continue 1:19:21 on that on that course thank you very much for your attention and for doing this 1:19:28 [Applause] 1:19:38 omar thank you spectacular presentation uh we do have a reception outside which 1:19:44 you're all invited to before we go i think it's only fair that we allow omar to answer at least a 1:19:50 couple of questions so i'd like to open the floor just for a couple of questions so please 1:19:59 peter so with this distributive production of 1:20:06 water which is a glorious idea it seems to me that there's got to be a 1:20:13 massive industrial scale synthetic job do you have an idea of the 1:20:18 scale of that and the cost of making an impact with this beautiful technology great so we understand her the question 1:20:25 is peace asking about industrial scale manufacturing of these materials well the mafs have already been you know we 1:20:32 worked with bsf for many years 17 years to show that moths can be scaled up to 1:20:37 multi-ton quantities that is already being done in water and in a synthetic procedure that allows 1:20:44 you to take the linker and the metal combine them and then get the linker and the metal 1:20:51 into the product no by-products so it's a completely 1:20:56 cyclable process and at the end of this the journey of the moth let's say in the device 1:21:02 you can add acid to the moth separate the metal from the linker and then reassemble it in water 1:21:09 in water so this has already been done and so 1:21:16 what else do we need okay do you want devices 1:21:21 that are engineered to trap water from the atmosphere using the moth where 1:21:28 the moth now is getting uh is is being placed in a 1:21:35 form it's not powdered moth in the in the device but it's placed in a form 1:21:40 that is like a coating on a substrate to maximize the exposure of the moth 1:21:47 to to air and so that you can take advantage of the full surface area that the moth provides you i just showed you 1:21:53 a device the beautiful thing about this device is that you can now correlate the molecular 1:22:00 aspects that we work so hard with with the not just the 1:22:07 substrate the mafia also but also the performance of the device 1:22:14 and the reason tiny changes into that absorptive site are very important is 1:22:20 because you're doing many cycles so even if i could improve 1:22:25 the absorption energy or the kinetics by a tiny amount that is insignificant in the 1:22:30 eyes of all chemists the device performance is improved in 1:22:35 that study i showed you 15 percent right that's a lot of that's a lot of water 1:22:41 in a in a device that we envision in that delivers 20 000 liters of water to 1:22:48 a village that just means so many more people that can get that can get water so i think in terms of 1:22:55 scalability is no different than any other new technology polymers remember polymers when they 1:23:01 were first discovered people said they're not scalable they're made from very expensive starting materials and so on but 1:23:09 if you create a need then the demand 1:23:15 the rest follows the technology works that's my point yeah 1:23:20 bloody has a question really beautiful talk 1:23:26 so i have a question you talk about application for water production 1:23:32 now the moth they have also very interesting properties when it comes to electronic and transport electric 1:23:38 transport so it and the spectronics would you comment something on that yeah 1:23:45 the questions about mafs relevance to electronics and conductivity and 1:23:51 charge charge transport we've done a lot of work on coughs in that direction 1:23:57 you can take a cough that is layered and through this stacking you can get 1:24:03 uh charge transport as good as uh graphene 1:24:10 okay so there's a lot of work being done in that in that right on conductive mafs on transport through mops 1:24:17 i think there we are looking for ways of taking the coughs and making 1:24:24 large areas of layers right so so that they could be 1:24:30 made useful in electronic applications and the applications that you're suggesting 1:24:38 so i would say that just depends on the building units and there's a lot of work that's being done there 1:24:44 you wanna don't i have a technical question the most beautiful though 1:24:49 um about hydrogen storage i'm a little bit confused so uh by 1:24:55 making this interplanetary natural structure i thought you wanted to increase the capacity but then actually 1:25:01 heat of air option increased so no no the heat absorption no i didn't i 1:25:08 was not clear the question is about the inter penetration whether that increase the heat of adsorption that that's not 1:25:14 actually true well the heat of absorption is the absorption is the energy of the hydrogen onto the 1:25:20 framework by doubling the up the by by doubling inter interpenetrating 1:25:25 that structure i close that open space that's not doing me any good right because the wall because the 1:25:32 hydrogen is no is not interacting with the surface and so it's still as if the 1:25:37 hydrogen is outside the moth so by introducing 1:25:42 another framework in now i've introduced more absorptive sites just like the ones 1:25:47 i already had but filling up that volume the absorption energy does not increase 1:25:53 in that situation because the nature of the absorption sites are exactly the same they just doubled yeah 1:25:59 yeah okay uh well actually i think we'll get petra 1:26:04 the last question and then omar is going to be outside we can ask questions of omar then so petra police 1:26:11 imagine that you can bring water to the villages but you have no electricity and no water so but when you 1:26:18 ideally would be your heating cooling device so then how you imagine we get electricity 1:26:24 for driving devices and start shooting panels or because 1:26:30 the more complicated the devices and the lower is the living time i think if you're you know good 1:26:37 question the question is about how are you going to use this device without elixir without 1:26:43 electricity in remote areas where there's no electric but i mean i showed you in the arizona device 1:26:50 that you could do this without without input of power aside from sunlight the 1:26:56 way the door can open and close engineers have materials that have actuators that could they could do that 1:27:02 depending on temperature so i think it's doable but i i just showed you how i can 1:27:09 harvest from one kilogram unoptimized and not all the kilogram is being used one cup 1:27:15 of water a day this could be a device sitting in a corner somewhere 100 kilos of this stuff 1:27:20 sitting in a corner some someplace and constantly harvesting water it could be significant for remote 1:27:26 areas in fact i feel like that application is much more impactful in the long run 1:27:31 because of the the fact that it's running on ambient sunlight um much more than the electrified device 1:27:39 but in yeah 1:27:46 because it was not on the ground one idea would be to vary let's say two thirds of the devices 1:27:52 exactly so then you could also do this practically you would you would have it in the column 1:27:58 and then you would would release the water practically in the sunshine exposing and this would 1:28:05 knock even in the desert because if you go deeper in the mountains yeah i mean i think that that's that's really 1:28:12 the idea i'm not suggesting that we could just take that box with a box within a box and put it 1:28:17 out there i'm just showing that the feasibility of that but there is some engineering that has to be 1:28:24 done but not requiring power that that needs to happen in order for this to work in a 1:28:30 uh you know in a reliable device yeah reliable meaning that the mechanics of 1:28:37 it is is not nothing's gonna break and it does not require constant maintenance 1:28:42 you know okay i think we should thank omar again 1:28:47 for absolutely spectacular presentation 1:28:56 you thanks Follow along using the transcript. 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