Fullerenes linked directly into a two-dimensional framework

Buckyballs can be used to build up a novel two-dimensional metal–organic framework (MOF). Unlike previous fullerene-based MOFs that incorporate fullerenes into pores or between layers, Ping Peng and colleagues at the University of Texas at El Paso, US, have used innovative fullerene derivatives as structure-directing linkers.

The fullerene derivatives have two pairs of phenyl pyridine groups attached to opposite ends of the C60 structure. Each molecule contributes one of its pyridyl group nitrogen atoms to form a rectangular-shaped ligand with three other hexakisfullerene derivatives, which coordinate to the same cadmium ion. Series of these coordination complexes produce two-dimensional sheets, with uncoordinated fullerene molecules filling the space between layers by sitting in the small pores created by the framework.

The group are now in the process of building a three-dimensional framework by joining the two-dimensional fullerene layer metal centres together using dipyridine-based pillars.