Electronic-Structure Tuning of Water-Splitting Nanocatalysts

Electrochemical water splitting (EWS) represents a promising pathway for the storage of intermittent energies, such as wind and solar, in the form of hydrogen gas. The operational efficiency of EWS is governed in part by the electrocatalysts for two electrode reactions, namely, the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). In this review, we highlight recent fundamental and experimental progress on tuning the electronic structure of electrocatalysts for enhanced EWS. In particular, we discuss several strategies to adjust the electronic structure of nanoelectrocatalysts, including: alloying, doping, interfacing, incorporating oxygen vacancies, and edge-defect engineering. Finally, some invigorating perspectives for future research directions are also provided.