Heterogeneous molecular catalysts based on transition metal complexes supported on conductive substrate have received increasing attention for their potential application in electrochemical energy conversion. In this talk I will report some progress made in our lab in this area. In one demonstration of heterogeneous molecular catalyst system based on Ni2+, we found for the first time that the presence of Fe3+ ions in the solution could bond at the vicinity of the Ni sites, generating heterogeneous Ni-Fe dual sites anchored on doped graphene. These Ni-Fe sites exhibited drastically improved oxygen evolution activity. Using CO2 reduction on well-defined molecular catalysts as a probe, we also demonstrated the importance of axial ligand and relay molecule in improving interfacial electron transfer and subsequent electrocatalytic activity.
