Interfacial engineering of Co5.47N/Mo5N6 nanosheets with rich active sites synergistically accelerates water dissociation kinetics for Pt-like hydrogen evolution

Yan Hu; Zhiyang Huang; Qing Zhang; Tayirjan Taylor Isimjan; Youqi Chu; Yongbiao Mu; Baoxin Wu; Zebing Huang; Xiulin Yang; Lin Zeng

doi:10.1016/j.jcis.2023.04.028

Interfacial engineering of Co_5.47N/Mo₅N₆ nanosheets with rich active sites synergistically accelerates water dissociation kinetics for Pt-like hydrogen evolution

J Colloid Interface Sci. 2023 Aug:643:455-464. doi: 10.1016/j.jcis.2023.04.028. Epub 2023 Apr 8.

Authors

Affiliations

¹ Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China; Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
² Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China.
³ Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
⁴ Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemistry and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004, China. Electronic address: xlyang@gxnu.edu.cn.
⁵ Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China. Electronic address: zengl3@sustech.edu.cn.

PMID: 37088049
DOI: 10.1016/j.jcis.2023.04.028

Abstract

The development of highly efficient hydrogen evolution electrocatalysts with platinum-like activity requires precise control of active sites through interface engineering strategies. In this study, a heterostructured Co_5.47N/Mo₅N₆ catalyst (CoMoN_x) on carbon cloth (CC) was synthesized using a combination of dip-etching and vapor nitridation methods. The rough nanosheet surface of the catalyst with uniformly distributed elements exposes a large active surface area and provides abundant interface sites that serve as additional active sites. The CoMoN_x was found to exhibit exceptional hydrogen evolution reaction (HER) activity with a low overpotential of 44 mV at 10 mA cm^-2 and exceptional stability of 100 h in 1.0 M KOH. The CoMoN_x^(-)||RuO₂⁽⁺⁾ system requires only 1.81 V cell voltage to reach a current density of 200 mA cm^-2, surpassing the majority of previously reported electrolyzers. Density functional theory (DFT) calculations reveal that the strong synergy between Co_5.47N and Mo₅N₆ at the interface can significantly reduce the water dissociation energy barrier, thereby improving the kinetics of hydrogen evolution. Furthermore, the rough nanosheet architecture of the CoMoN_x catalyst with abundant interstitial spaces and multi-channels enhances charge transport and reaction intermediate transportation, synergistically improving the performance of the HER for water splitting.

Keywords: Co(5.47)N/Mo(5)N(6); Density functional theory; Hydrogen evolution; Rough nanosheet; Synergistic effect.