Recent Progress of Advanced Electrocatalysts for Hydrogen Production via Hydrazine-assisted Water Electrolysis

Abstract

Coupling thermodynamic favorable hydrazine oxidation reaction (HzOR) with hydrogen evolution reaction (HER) in a hybrid water electrolyzer is an effective strategy to improve the energy efficiency of large-scale high-purity H2 production and simultaneously realize pollutant degradation. Recently, various advanced materials have been exploited as electrocatalysts for hydrazine-assisted water electrolysis, but the fundamental understanding and comprehensive summary is lacking to date. In this review, we provide a comprehensive review of the advanced electrocatalysts for HzOR-assisted water electrolysis, including various regulatory strategies based on precious metals and non-noble metal-based materials, such as doping, heterostructure, single-atom and alloying. Moreover, the structure-activity relationship between electronic structure, surface properties and catalytic performance of the electrocatalysts is systematically discussed. In view of the importance and unique advantages of direct hydrazine hydrate-assisted seawater electrolysis and self-powered electrolyzer, we also carry out systematic summary based on material design, performance evaluation, and mechanism study. Finally, several key challenge and future perspective of hydrazine-assisted water electrolysis are proposed and discussed to offer insight for the large-scale H2 production in energy-saving pathway.