A metal/semiconductor contact induced Mott–Schottky junction for enhancing the electrocatalytic activity of water-splitting catalysts

Abstract

Hydrogen, with clean and high gravimetric energy density features, has been considered as an ideal energy carrier. Electrochemical water splitting that can convert the intermittent electricity generated from wind and solar energy into storable hydrogen is a promising technique. The large-scale utilization of water electrolysis is constrained by the sluggish hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Therefore, cost-effective and highly efficient electrocatalysts are needed to reduce the intrinsic energy barriers and thus enhance the energy conversion efficiency. The Mott–Schottky junction at the metal/semiconductor interface can modulate the electron density of active sites and optimize the chemisorption of water-splitting intermediates via the Mott–Schottky effect, and thus is drawing growing attention. Herein, we summarize the recent advances in Mott–Schottky electrocatalysts for the OER, HER, and overall water-splitting. Specifically, the strategies for preparing Mott–Schottky catalysts and the relationships between the structure/composition and catalytic performance are profoundly discussed. Finally, the challenges and prospects for the future development and application of Mott–Schottky catalysts in water electrolysis are briefly discussed.