Electrochemical CO2 reduction to C2+ products with Cu-oleylamine based nanoparticles synthesized by simple thermal treatment

• Published in: Fuel (Guildford) Vol. 348; p. 128498
• Main Authors: Liu, Xinyu, Li, Jingzheng, Xue, Yuan, Gong, Mingxing, Cabrera, Carlos R., Yao, Lin, Hu, Zhongfa
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 15.09.2023
• Subjects: CO2RR; Copper oxides; Grain boundary; Lattice mismatch; Oleylamine; CO2RR; Copper oxides; Lattice mismatch; Oleylamine; Grain boundary
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2023.128498

The grain boundary and lattice mismatch among CuO and Cu2O work properly to facilitate the formation of ethylene and C2+ products during CO2RR. [Display omitted] •Cu catalysts were prepared by thermal reduction of organic copper reagent complexation.•CuOAm reduced at 180 °C exhibits FEs as 79% for C2+ products.•Grain boundary and lattice mismatch formed due to different crystal structures.•In-situ Raman measurements confirms catalyst reconstruction and reaction pathways. Cu-based catalysts for CO2 electrochemical reduction reaction suffer from both activity and selectivity towards C2+ products. Here, Cu-Oleylamine (CuOAm) based catalysts with adjustable Cu chemical state are synthesized through thermal reducing method with oleylamine as the only surfactant, solvent, and reducing agent. The catalyst exhibits a high faradaic efficiency of 54% and 79% with a partial current density of 186 mA cm−2 and 245 mA cm−2 at −1.0 V (vs. RHE) for C2H4 and C2+ products, respectively. Further characterizations of the size, morphology and surface composition of CuOAm by XRPD, XPS, SEM, HRTEM, and EDS showed that the presence of different crystal structures (CuO and Cu2O) with comparable amounts were vital for the formation of grain boundary and lattice mismatch during CO2RR. The sequential reduction of CuOx and CO2 at abundant grain boundary and lattice mismatch could facilitate the formation of ethylene and C2+ products, which was confirmed by in-situ Raman measurements under varied potentials.