Optimized Electronic Modification of S-Doped CuO Induced by Oxidative Reconstruction for Coupling Glycerol Electrooxidation with Hydrogen Evolution

• Published in: Nano-micro letters Vol. 15; no. 1; p. 190
• Main Authors: Fan, Ruo-Yao, Zhai, Xue-Jun, Qiao, Wei-Zhen, Zhang, Yu-Sheng, Yu, Ning, Xu, Na, Lv, Qian-Xi, Chai, Yong-Ming, Dong, Bin
• Format: Journal Article
• Language: English
• Published: Singapore Springer Nature Singapore 01.12.2023; Springer Nature B.V; SpringerOpen
• Subjects: Arrays; Asymmetry; Coupling; Covalent bonds; CuO; Electrocatalysis; Electrocatalysts; Electrolytic cells; Electronic modification; Engineering; Formic acid; Glycerol; Glycerol oxidation reaction (GOR); Glycolic acid; Hydrogen; Hydrogen evolution reaction (HER); Hydrogen evolution reactions; Hydrogen production; Leaching; Nanorods; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; Noble metals; Oxidation; Oxidative reconstruction; Oxygen; Sulfur; Transition metals; Hydrogen evolution reaction (HER); CuO; Electronic modification; Oxidative reconstruction; Glycerol oxidation reaction (GOR)
• ISSN: 2311-6706; 2150-5551
• DOI: 10.1007/s40820-023-01159-6

Highlights S-doped CuO nanorod arrays (S-CuO/CF) constructed by sulfur leaching and oxidative remodeling strategy require only 1.23 and 1.33 V versus hydrogen evolution reaction (HER) to provide glycerol oxidation currents of 100 and 500 mA cm −2 . S-CuO/CF shows satisfactory performance (at 100 mA cm −2 , V cell  = 1.37 V) assembled as the anode in asymmetric coupled electrolytic cell of glycerol oxidation reaction and HER. The study identifies the key factors involved in the GOR reaction pathway, which include the C–C bond breaking and lattice oxygen deintercalation steps. Glycerol (electrochemical) oxidation reaction (GOR) producing organic small molecule acid and coupling with hydrogen evolution reaction is a critical aspect of ensuring balanced glycerol capacity and promoting hydrogen generation on a large scale. However, the development of highly efficient and selective non-noble metal-based GOR electrocatalysts is still a key problem. Here, an S-doped CuO nanorod array catalyst (S-CuO/CF) constructed by sulfur leaching and oxidative remodeling is used to drive GOR at low potentials: It requires potentials of only 1.23 and 1.33 V versus RHE to provide currents of 100 and 500 mA cm −2 , respectively. Moreover, it shows satisfactory comprehensive performance (at 100 mA cm −2 , V cell  = 1.37 V) when assembled as the anode in asymmetric coupled electrolytic cell. Furthermore, we propose a detailed cycle reaction pathway (in alkaline environment) of S-doped CuO surface promoting GOR to produce formic acid and glycolic acid. Among them, the C–C bond breaking and lattice oxygen deintercalation steps frequently involved in the reaction pathway are the key factors to determine the catalytic performance and product selectivity. This research provides valuable guidance for the development of transition metal-based electrocatalysts for GOR and valuable insights into the glycerol oxidation cycle reaction pathway.