Three-Dimensional N-Doped Graphene Coated with B-Doped Iron Phosphide Electrocatalysts: Nonmetallic Element Co-Modification for Enhanced Dual-Ph Hydrogen Evolution Reaction

Abstract

The construction of cost-effective and highly active transition metal phosphide-based electrocatalysts instead of noble metals through a feasible strategy is crucial for addressing the energy crisis. Herein, a novel three-dimensional structure N-doped RGO coated with a ‘worm-like’ B-doped FeP electrocatalyst (B-FeP/N-RGO) was successfully developed using a multi-step reaction. The composite catalyst possesses a unique three-dimensional structure that facilitates rapid mass transfer, gas release and exposure of abundant active sites, and non-metallic element doping optimizes the electronic structure of the matrix, which together improve the hydrogen evolution reaction performance. Notably, the B-FeP/N-RGO catalysts can achieve a current density of 10 mA cm-2 in both acidic and alkaline electrolytes with overpotentials of only 125 and 176 mV, while maintaining long-term stability. This study offers a promising approach for designing and fabricating highly efficient three-dimensional electrocatalysts that do not rely on noble-metals and are suitable for a wide pH range.

Keywords: three-dimensional N-RGO, iron phosphide, hydrogen evolution reaction, wide pH range, electrocatalysis