Template-assisted Fabrication of O-doped CoP Microflowers with Optimal Electronic Modulation for Electrochemical Hydrogen Evolution

Chemistry. 2023 Jul 20;29(41):e202301252. doi: 10.1002/chem.202301252. Epub 2023 Jun 12.

Abstract

Exploring efficient, affordable and stable electrocatalyst toward hydrogen evolution reaction (HER) is of great scientific significance for the practical implementation of the water splitting. The heteroatom doping represents a serviceable strategy to further elevate the catalytic performance for a transition metal-based electrocatalyst because of the electronic regulation effect. Herein, a reliable self-sacrificial template-engaged approach is proposed to synthesize O-doped CoP (denoted as O-CoP) microflowers, which simultaneously considers the regualtion of electronic configuration via anion doping and sufficient exposure of active sites via nanostructure engineering. The suitable O incorporation content in CoP matrix could tremendously modify the electronic configuration, accelerate the charge transfer, promote the exposure of active sites, strengthen the electrical conductivity, and adjust the adsorption state of H*. Consequently, the optimized O-CoP microflowers with optimal O concentration display a remarkable HER property with a small overpotential of 125 mV to afford a current density of 10 mA cm-2 , a low Tafel slope of 68 mV dec-1 and long-term durability for 32 h under alkaline electrolyte, manifesting a considerable potential application for hydrogen production at large scale. The integration of anion incorporation and architecture engineering in this work will bring in a depth insight for the design of low-cost and effective electrocatalysts in energy conversion and storage systems.

Keywords: O incorporation; O-CoP microflowers; electronic modulation; hydrogen evolution reaction.