MOF-derived NiCo bimetallic cocatalyst for enhanced photocatalytic overall water splitting

Abstract

The development of stable and efficient non-noble metal cocatalysts has arisen as a promising yet challenging endeavor in the context of photocatalytic overall water splitting. In this study, NiCo alloy cocatalysts were synthesized with nickel/cobalt metal organic framework (NiCo-MOF) as source of nickel and cobalt. Systematic characterization results demonstrate the successful deposition of alloy cocatalysts onto the surface of SrTiO₃. The prepared SrTiO₃ loaded NiCo-alloy can generate hydrogen and oxygen in a stoichiometric ratio for photocatalytic overall water splitting, achieving an apparent quantum yield of 11.9% at 350 ± 10 nm. Theoretical calculations indicate that the introduction of cobalt has a beneficial regulatory effect on the hydrogen evolution sites of Ni, reducing the free energy of H adsorption. The synergistic catalytic effect of bimetallic catalysts contributes to enhancing photocatalytic activity and stability. This study offers constructive insights for the development of high-efficiency and cost-effective cocatalyst systems.