Development of CO2-reducing electrocatalysts utilizing non-precious metals supported by pincer ligand scaffolds

Abstract

The electrocatalytic redn. of carbon dioxide to form usable fuels such as formate, methanol, or higher-order hydrocarbons is an ideal method for alternative energy storage. Compared to heterogenous systems, mol. catalysts are generally more selective, more easily tuned, and allow for detailed mechanistic studies. However, a catalyst remains to be found which is highly stable, utilizes an earth-abundant metal, and operates at a low overpotential with a high rate. Late transition metal complexes supported by pincer ligands have been shown to promote CO_2 insertion into metal-hydride bonds and catalytic CO_2 hydrogenation. Furthermore, efficient and selective electrochem. redn. of CO_2 to formate has been achieved with a PCP-iridium complex in the presence of a proton source. In this study, we evaluate the potential for iron, cobalt, and nickel complexes supported by PNP and PCP pincer ligands to provide a more cost-effective platform for electrochem. CO_2 redn.