Built-in Electric Field-Induced Work Function Reduction in C-Co3O4 for Efficient Electrochemical Nitrogen Reduction

Shuyuan Li; Rui Zhao; Xinyue Chi; Xiaoxuan Wang; Yixiang Zhou; Yuanyuan Xiong; Yebo Yao; Dewei Wang; Zhenzhen Fu; Jiangzhou Xie; Yi-Ming Yan

doi:10.1021/acs.jpclett.3c02205

Built-in Electric Field-Induced Work Function Reduction in C-Co₃O₄ for Efficient Electrochemical Nitrogen Reduction

J Phys Chem Lett. 2023 Oct 5;14(39):8828-8836. doi: 10.1021/acs.jpclett.3c02205. Epub 2023 Sep 26.

Authors

Affiliations

¹ State Key Lab of Organic-Inorganic Composites, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing 100029, People's Republic of China.
² School of Mechanical and Manufacturing Engineering, University of New South Wales, Sydney, New South Wales 2052, Australia.

PMID: 37751210
DOI: 10.1021/acs.jpclett.3c02205

Abstract

Co₃O₄ is a highly selective catalyst for the electrochemical conversion of N₂ to NH₃. However, the large work function (WF) of Co₃O₄ leads to unsatisfactory activity. To address this issue, a strong built-in electric field (BIEF) was constructed in Co₃O₄ by doping C atoms (C-Co₃O₄) to reduce the WF for improving the electrocatalytic performance. C-Co₃O₄ exhibited a remarkable NH₃ yield of 38.5 μg h^-1 mg_cat^-1 and a promoted FE of 15.1% at -0.3 V vs RHE, which were 2.2 and 1.9 times higher than those of pure Co₃O₄, respectively. Kelvin probe force microscopy (KPFM), zeta potential, and ultraviolet photoelectron spectrometry (UPS) confirmed the formation of strong BIEF and WF reduction in C-Co₃O₄. Additionally, in situ Raman measurements and density functional theory (DFT) calculations revealed the relationship between BIEF and WF and provided insights into the reaction mechanism. Our work offers valuable guidance for the design and development of more efficient nitrogen reduction catalysts.