Nitrogen-Doped CoP Electrocatalysts for Coupled Hydrogen Evolution and Sulfur Generation with Low Energy Consumption

Qingwen Zhou; Zihan Shen; Chao Zhu; Jiachen Li; Zhiyuan Ding; Peng Wang; Feng Pan; Zhiyong Zhang; Haixia Ma; Shuangyin Wang; Huigang Zhang

doi:10.1002/adma.201800140

Nitrogen-Doped CoP Electrocatalysts for Coupled Hydrogen Evolution and Sulfur Generation with Low Energy Consumption

Adv Mater. 2018 Jul;30(27):e1800140. doi: 10.1002/adma.201800140. Epub 2018 May 17.

Authors

Qingwen Zhou¹, Zihan Shen¹, Chao Zhu¹, Jiachen Li², Zhiyuan Ding¹, Peng Wang¹, Feng Pan³, Zhiyong Zhang⁴, Haixia Ma², Shuangyin Wang⁵, Huigang Zhang¹

Affiliations

¹ National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Institute of Materials Engineering, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Jiangsu, 210093, China.
² Department of Chemical Engineering, Northwest University, Shaanxi, 710069, China.
³ School of Advanced Materials, Peking University, Shenzhen Graduate School, Shenzhen, Guangdong, 518055, China.
⁴ School of Information Science and Technology, Northwest University, Shaanxi, 710127, China.
⁵ College of Chemistry and Chemical Engineering, Hunan University, Changsha, Hunan, 410012, China.

PMID: 29774606
DOI: 10.1002/adma.201800140

Abstract

Hydrogen production is the key step for the future hydrogen economy. As a promising H₂ production route, electrolysis of water suffers from high overpotentials and high energy consumption. This study proposes an N-doped CoP as the novel and effective electrocatalyst for hydrogen evolution reaction (HER) and constructs a coupled system for simultaneous hydrogen and sulfur production. Nitrogen doping lowers the d-band of CoP and weakens the H adsorption on the surface of CoP because of the strong electronegativity of nitrogen as compared to phosphorus. The H adsorption that is close to thermos-neutral states enables the effective electrolysis of the HER. Only -42 mV is required to drive a current density of -10 mA cm^-2 for the HER. The oxygen evolution reaction in the anode is replaced by the oxidation reaction of Fe²⁺ , which is regenerated by a coupled H₂ S absorption reaction. The coupled system can significantly reduce the energy consumption of the HER and recover useful sulfur sources.

Keywords: cobalt phosphide; electrocatalyst; hydrogen evolution reaction; nitrogen doping; sulfur recovery.