FeOx/FeP hybrid nanorods neutral hydrogen evolution electrocatalysis: insight into interface

Abstract

The electrocatalytic interface plays a crucial role in driving the water splitting reaction. Herein, we report a rational constructed interface of Fe–O–P hybrid nanorods co-catalyst playing a significant role in high-performance hydrogen generation from neutral water. It is worth noting that the FeO_x/FeP hybrid structure exhibits remarkably low overpotential of 96 mV at a current density of 10 mA cm⁻² with a small Tafel slope of 47 mV dec⁻¹ and maintains excellent electrolytic durability over 60 h, placing it at the forefront among the best hydrogen evolution electrocatalysts operating in neutral media. The increased Tafel value contributed by FeO_x elimination demonstrates the important effect of the FeO_x/FeP interface. Additionally, theoretical investigations reveal deeper insights into the FeO_x/FeP interface: firstly, the FeO_x facilitates the adsorption and dissociation of water molecules and accelerates the supply of hydrogen atoms in the Volmer–Heyrovsky reaction; secondly, the interface further optimizes the Gibbs free energy for hydrogen adsorption at the FeP surface.