Recent advances in hybrid water electrolysis for energy-saving hydrogen production

Electricity-driven water splitting to convert water into hydrogen (H2) has been widely regarded as an efficient approach for H2 production. Nevertheless, the energy conversion efficiency of it is greatly limited due to the disadvantage of the sluggish kinetic of oxidation evolution reaction (OER). To effectively address the issue, a novel concept of hybrid water electrolysis has been developed for energy–saving H2 production. This strategy aims to replace the sluggish kinetics of OER by utilizing thermodynamically favorable organics oxidation reaction to replace OER. Herein, recent advances in such water splitting system for boosting H2 evolution under low cell voltage are systematically summarized. Some notable progress of different organics oxidation reactions coupled with hydrogen evolution reaction (HER) are discussed in detail. To facilitate the development of hybrid water electrolysis, the major challenges and perspectives are also proposed.