Co porphyrin-based metal-organic framework for hydrogen evolution reaction and oxygen reduction reaction

Constructing molecule@support composites is an attractive strategy to realize heterogeneous molecular electrocatalysis.Herein,we synthesized metal-organic framework(MOF)-supported molecular catalysts for hydrogen evolution and oxygen reduction reaction(HER/ORR).Ligand exchange strategy was used to prepare molecule@support hybrids due to the same functional group.A series of hybrids were obtained using Co porphyrin(1)and different MOFs including MIL-88(Fe),MOF-5(NiCo)and UIO-66(Zr).The1@MOF-5(NiCo)had the best HER and ORR activity compared with 1@MIL-88(Fe)and 1@MOF-5(NiCo).These hybrids also exhibited tunable selectivity for ORR with four-electron process,which can be attributed to the synergistic effect of porphyrin molecules and MOFs.This work provides a possibility for molecular catalysts to improve activity of HER and tune selectivity of ORR.