Multivariate MOFs make the case for embracing complexity

Omar Yaghi is convinced that chemists should embrace complexity. ‘Right now, materials in general have one structure, one property, one operation,’ he says. ‘[Yet] it would be great if we could design materials… where several things are happening at once.’

This is surprising for a chemist who helped establish the field of metal–organic frameworks (MOFs), a contribution recognised by last year’s Nobel prize in chemistry, which Yaghi shared with Susumu Kitagawa and Richard Robson. Yet in recent years, Yaghi has moved away from creating conventional MOFs built from a single type of linker and metal node. Instead, he and other chemists have found ways to incorporate multiple organic ligands and different metal building blocks within a single structure.

This new class of materials – known as multivariate- or MTV-MOFs – drastically expands the scope and capability of porous frameworks. ‘[Chemists] look at [MTV-MOFs] and they say “Oh my God, this is just in one structure? You have too many things happening”,’ says Yaghi. ‘A lot of people shy away from it [but] I think that [it’s] a big opportunity to transform our chemistry.’