Coordinated single-molecule micelles: a self-template approach for preparing mesoporous doped carbons.

Porous carbons prepared using a self-template approach inherit the pore features of template, but they exhibit almost no evenly dispersed mesopores, which is significant for diffusion-limited applications. Herein, N-doped hierarchically porous carbons (NHPCs) with uniform mesopores are prepared using a self-template method. The spherical single-molecule micelle of polystyrene--poly(4-vinyl pyridine) (PS--P4VP) is turned into a Zn-coordinated PS--P4VP micelle (CPM) by coordination of Zn with the P4VP shell. Then, the self-template of the CPM is carbonized into a hollow carbon nanosphere. During carbonization, the PS core is decomposed to generate the central mesopore, whereas the Zn-coordinated P4VP shell is transformed into a carbonaceous shell. These even hollow carbon nanospheres aggregate to form uniformly mesoporous carbon lumps. Simultaneously, the coordinated Zn of the CPM is reduced to metal zinc at high temperatures and then it is evaporated, thus creating numerous micropores in the carbonaceous shell. These NHPCs with uniform mesopores display a high specific surface area. As a demonstration in diffusion-limited applications, their catalytic performances for the oxygen reduction reaction (ORR) are investigated. Strikingly, NHPCs exhibit outstanding catalytic performances for the ORR. This self-template method paves a facile approach for preparing mesoporous carbons with high performances.