Modulating the electronic structure of CoS2 by Sn doping boosting urea oxidation for efficient alkaline hydrogen production

Yong-Zheng Wu; Yuan Huang; Li-Wen Jiang; Chao Meng; Zhao-Hua Yin; Hong Liu; Jian-Jun Wang

doi:10.1016/j.jcis.2023.03.165

Modulating the electronic structure of CoS₂ by Sn doping boosting urea oxidation for efficient alkaline hydrogen production

J Colloid Interface Sci. 2023 Jul 15:642:574-583. doi: 10.1016/j.jcis.2023.03.165. Epub 2023 Mar 30.

Authors

Yong-Zheng Wu¹, Yuan Huang¹, Li-Wen Jiang¹, Chao Meng¹, Zhao-Hua Yin¹, Hong Liu², Jian-Jun Wang³

Affiliations

¹ State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, Shandong, China.
² State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, Shandong, China; Institute for Advanced Interdisciplinary Research (IAIR), University of Jinan, Jinan 250022, Shandong, China. Electronic address: hongliu@sdu.edu.cn.
³ State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, Shandong, China. Electronic address: wangjianjun@sdu.edu.cn.

PMID: 37028164
DOI: 10.1016/j.jcis.2023.03.165

Abstract

Urea electrocatalytic oxidation afforded by renewable energies is highly promising to replace the sluggish oxygen evolution reaction in water splitting for hydrogen production while realizing the treatment of urea-rich waste water. Therefore, the development of efficient and cost-effective catalysts for water splitting assisted by urea is highly desirable. Herein, Sn-doped CoS₂ electrocatalysts were reported with the engineered electronic structure and the formation of Co-Sn dual active sites for urea oxidation reaction (UOR) and hydrogen evolution reaction (HER), respectively. Consequently, the number of active sites and the intrinsic activity were enhanced simultaneously and the resultant electrodes exhibited outstanding electrocatalytic activity with a very low potential of 1.301 V at 10 mA·cm^-2 for UOR and an overpotential of 132 mV at 10 mA·cm^-2 for HER. Therefore, a two-electrode device was assembled by employing Sn(2)-CoS₂/CC and Sn(5)-CoS₂/CC and the constructed cell required only 1.45 V to approach a current density of 10 mA·cm^-2 along with good durability for at least 95 h assisted by urea. More importantly, the assembled electrolyzer can be powered by commercial dry battery to generate numerous gas bubbles on the surface of the electrodes, demonstrating the high potential of the as-fabricated electrodes for applications in hydrogen production and pollutant treatment at a low-voltage electrical energy input.

Keywords: Cobalt sulfide; Electronic structure; Sn doping; Surface reconstruction; Urea-assisted water splitting.