Carbon-Encapsulated WOx Hybrids as Efficient Catalysts for Hydrogen Evolution

Shengyu Jing; Jiajia Lu; Guangtao Yu; Shibin Yin; Lin Luo; Zengsong Zhang; Yanfeng Ma; Wei Chen; Pei Kang Shen

doi:10.1002/adma.201705979

Carbon-Encapsulated WO_x Hybrids as Efficient Catalysts for Hydrogen Evolution

Adv Mater. 2018 Jul;30(28):e1705979. doi: 10.1002/adma.201705979. Epub 2018 May 29.

Authors

Shengyu Jing¹, Jiajia Lu^{1

2}, Guangtao Yu³, Shibin Yin², Lin Luo², Zengsong Zhang³, Yanfeng Ma³, Wei Chen³, Pei Kang Shen²

Affiliations

¹ School of Information and Control Engineering, China University of Mining and Technology, Xuzhou, 221116, P. R. China.
² Guangxi Key Laboratory of Electrochemical Energy Materials, Collaborative Innovation Center of Renewable Energy Materials (CICREM), State Key Laboratory of Processing for Non-Ferrous Metal and Featured Materials, Guangxi University, Nanning, 530004, P. R. China.
³ Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, International Joint Research Laboratory of Nano-Micro Architecture Chemistry, Jilin University, Changchun, 130023, P. R. China.

PMID: 29845654
DOI: 10.1002/adma.201705979

Abstract

Developing non-noble metal catalysts as Pt substitutes, with good activity and stability, remains a great challenge for cost-effective electrochemical evolution of hydrogen. Herein, carbon-encapsulated WO_x anchored on a carbon support (WO_x @C/C) that has remarkable Pt-like catalytic behavior for the hydrogen evolution reaction (HER) is reported. Theoretical calculations reveal that carbon encapsulation improves the conductivity, acting as an electron acceptor/donor, and also modifies the Gibbs free energy of H* values for different adsorption sites (carbon atoms over the W atom, O atom, WO bond, and hollow sites). Experimental results confirm that WO_x @C/C obtained at 900 °C with 40 wt% metal loading has excellent HER activity regarding its Tafel slope and overpotential at 10 and 60 mA cm^-2 , and also has outstanding stability at -50 mV for 18 h. Overall, the results and facile synthesis method offer an exciting avenue for the design of cost-effective catalysts for scalable hydrogen generation.

Keywords: carbon-encapsulated WOx; catalysts; density functional theory; hydrogen evolution reaction; stability.