Hierarchical molybdenum phosphide coupled with carbon as a whole pH-range electrocatalyst for hydrogen evolution reaction

Abstract

In the effort to develope more effective electrocataysts for water electrolysis hydrogen generation through hydrogen evolution reaction (HER), the well-crystallized molybdenum phosphide nanoparticles dispersed in three-dimensional N,P-codoped graphite carbon nanosheets (3D MoP/NPG) are synthesized in this work using a SiO2-template-assisted strategy. Instrument characterization shows that the catalyst has a large specific surface area, high electrical conductivity, and the coupled interfaces & synergistic effect between MoP and carbon sheets toward electrocatalytic HER. Experimental results reveal that MoP/NPG possesses remarkable catalytic HER activity and stability in a wide pH range. Density functional theory (DFT) calculations reveal that the coupled interaction between MoP and carbon sheet interfaces can induce an optimal free energy of hydrogen adsorption on the catalyst surface. Both the theoretical calculations and experimental results demonstrate that the hierarchical structure with synergistic interaction between MoP and carbon sheets can facilitate charge transfer kinetics to enhance HER performance.