Ampere-level hydrogen production from hydrazine assisted water splitting by Pt-decorated Co3W alloy.

Abstract

Hydrazine-assisted water electrolysis offers an energy-efficient route for hydrogen production. However, rational regulation of the electronic structure of active sites to simultaneously optimize the hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR) remains a critical challenge. Herein, we report a strategy for constructing a high-performance bifunctional electrode by integrating Pt clusters onto a highly conductive Co3W alloy support for energy-efficient hydrazine-assisted water splitting. The metallic nature of Co3W not only ensures rapid electron transport but also enables strong interfacial charge redistribution at the Pt-Co3W interface, thereby effectively modulating the d-band center of the catalyst. Operando spectroscopic analyses and theoretical calculations demonstrate that the incorporation of Pt site optimizes the adsorption/desorption behavior of key reaction intermediates and significantly lowers the energy barrier of the rate-determining steps for both HER and HzOR. As a result, the optimized Pt@Co3W/NF electrode exhibits excellent bifunctional catalytic activity in a two-electrode hydrazine-assisted water electrolyzer. It delivers a low cell voltage of 0.36 V at 1000 mA cm-2, a hydrogen faradaic efficiency (FE) exceeding 96%, and remarkable long-term stability over 144 h. this work provides important insights into the design of efficient bifunctional electrocatalysts for sustainable energy applications.