A pore-expansion strategy to synthesize hierarchically porous carbon derived from metal-organic framework for enhanced oxygen reduction

We introduced a pore-expansion strategy to transform metal-organic framework (MOF) into foam-like carbons with high surface area and hierarchical pores. A typical kind of MOF was chosen as the starting material. The catalytic carbon, which displayed a remarkably enlarged surface area and high pore volume, was prepared by a solvent-assistant-linker-exchange method and a following pore-expansion carbonization process. Interestingly, the catalytic carbon possessed a hierarchically porous structure in which micro-, meso- and macro-pores coexisted. Benefiting from the structural merits, it showed superior catalytic performance towards oxygen reduction reaction (ORR). This work emphasizes the importance of interconnecting structures with hierarchical pores towards ORR and opens a new avenue to fabricate advanced nanostructures from MOFs for enhanced electrochemical applications.