Development of molecular electrocatalysts for hydrogen generation and utilization

Catalysts capable of efficient conversion between electrical energy and fuels will be important for a flexible and sustainable energy supply in the future. Renewable energy sources, such as solar and wind, are intermittent and will require large scale energy storage. An attractive approach to storing this energy is the generation of fuels such as hydrogen. In recent work we have developed nickel complexes containing diphosphine ligands with pendant bases as electrocatalysts for hydrogen oxidation and production. The development of these catalysts has been guided by an understanding of the contributions of both the first and second coordination spheres of these catalysts. Pendant bases incorporated in the second coordination sphere of the molecular catalysts for H2 production and oxidation serve as proton relays controlling the movement of protons between the metal and acids or bases in solution. Insights into additional roles played by the pendant bases during the catalytic cycles will be discussed.