Modulating the electronic interactions via heterostructure engineering for energy-saving hydrogen production at high current densities

Abstract

Advanced alkaline hydrogen evolution reaction (HER) catalysts should exhibit a low water dissociation energy barrier and fast reaction kinetics. However, single-component transition metal catalysts typically show insufficient activation of water, leading to unsatisfactory electrocatalytic activity. Rationally modulating the composition and constructing heterogeneous interfaces can effectively regulate the interfacial electronic structure of catalysts, thereby improving the kinetics and catalytic activity of the alkaline HER. Herein, Ni_0.2Mo_0.8N/F,N–C@NF heterogeneous catalyst was prepared, demonstrating excellent alkaline HER activity (281 mV @ 1000 mA cm⁻²). Experimental results and density functional theory (DFT) calculations indicate that heterogeneous engineering can effectively modulate the surface charge structure of catalysts, enhancing the adsorption and activation of reactive intermediates. Simultaneously, heterogeneous engineering accelerates reaction kinetics by further reducing the energy barrier of the Tafel step. The Ni_0.2Mo_0.8N/F,N–C@NF catalyst also exhibits satisfactory catalytic activity towards the HER when integrated with a methanol oxidation reaction. This work provides an effective guide for the rational design of high-performance alkaline HER electrocatalysts for energy-saving hydrogen production.