Can molecular Lego save the planet?

{"text":[[{"start":null,"text":"

"}],[{"start":7.13,"text":"The writer is a science commentator"}],[{"start":11.18,"text":"The idea struck Richard Robson, a British-born chemist at Melbourne University, as he was building large wooden models of crystals to show in undergraduate lectures. Diamond, for example, is a repeating pattern where each carbon atom binds to four other carbon atoms in a tetrahedral pattern — and easily duplicated with wooden balls representing carbon atoms and rods for chemical bonds."}],[{"start":41.66,"text":"What if, Robson pondered in the 1970s, metals and organic (carbon-based) molecules could link up to make similar kinds of 3D patterns? Around a decade later, his experiments showed that metal ions (metal atoms that carry a charge) and organic molecules could indeed form a viable crystal structure: an infinitely repeating pattern filled with vast spaces, making the material a porous sponge."}],[{"start":77,"text":"Last week, Robson, together with Susumu Kitagawa from Kyoto University, and Omar Yaghi, from the University of California, Berkeley, won the Nobel Prize in Chemistry for developing what the citation committee lauded as “a new form of molecular architecture”. The field they pioneered — called metal-organic frameworks, or MOFs, and sometimes described as molecular Lego — matters because it could change the world."}],[{"start":108.78999999999999,"text":"MOFs are being touted — and tested — as versatile, scalable, customisable fixes for atmospheric and industrial challenges: mopping up pollutants, including carbon and so-called forever chemicals; snatching water from desert air; catalysing chemical reactions; storing and releasing hydrogen; and converting toxic substances into benign ones.  "}],[{"start":135.82999999999998,"text":"The human stories behind this year’s chemistry prize are also surprising. Robson thought himself a second-rate scholar for not being a mathematician and sat on his ideas for several years before testing them. Yaghi was born in Jordan to Palestinian refugee parents, with his family and their cattle sharing one room, before leaving aged 15 for the US. Kitagawa, meanwhile, was originally researching high-density materials before he suddenly grasped the potential of very porous ones. All, according to interviews, were driven by pure curiosity rather than by any grand vision for solving global problems."}],[{"start":186.26999999999998,"text":"While Robson, now 88, came up with the idea of metal ions linked by organic molecule struts, the first material he devised in the lab was unstable. By the early 2000s, Yaghi and Kitagawa had separately found ways of making these cavity-filled crystalline structures stable and flexible. Between them, the three men, who shared the 11mn Swedish Kronor ($1.15mn) prize equally, had conjured up a new world of materials."}],[{"start":223.35999999999999,"text":"Chemists can take a mix-and-match approach to the constituent metals and organic molecules, to make the pores smaller or bigger, or shape them to trap specific substances; more than 90,000 different MOFs have been synthesised so far. “If you think it, you can make it,” Yaghi told a press conference last week."}],[{"start":245.04,"text":"One astonishing characteristic is the amount of surface area locked away in these new materials: a MOF weighing one gramme can have an internal surface area the size of a football pitch. MOFs are often likened to Hermione Granger’s bottomless handbag in the Harry Potter books: a tiny exterior concealing a seemingly infinite interior. Rice University chemist Stavroula Alina Kampouri has called MOFs “magical sponges”, describing them as “not just elegant crystals you’d admire under a microscope; they’re an entire universe of structures, each like a miniature city of tunnels and rooms waiting to be filled.” "}],[{"start":291.12,"text":"Given the sheer number of permutations of metals and organic molecules that can be combined, companies are turning to AI to identify promising candidates for different applications. Meta has been building a database of MOFs potentially able to capture carbon dioxide from the atmosphere — but in July that project drew criticism for being over-optimistic. The field is also fertile ground for start-ups: in February, the journal Nature Materials counted about 50 MOF-based companies; IBM is also taking an interest. One company, AirJoule, recently began working with a data centre developer to evaluate MOF technology for extracting water from waste heat."}],[{"start":346.21000000000004,"text":"After the prize was announced, Robson told the First Reactions podcast that he drifted into chemistry because “I couldn’t think of anything better to do.” Yaghi became hooked at 10 after seeing pictures of molecules in a library book, adding humbly: “Science is the greatest equalising force in the world.” Their remarks seem somehow appropriate: outwardly modest but concealing vast, intellectual depths."}],[{"start":385.52,"text":""}]],"url":"https://audio.ftcn.net.cn/album/a_1761034123_7743.mp3"}