Atomically dispersed cerium on copper tailors interfacial water structure for efficient CO-to-acetate electroreduction
Peng‐Peng Yang, Zhi‐Zheng Wu, Ye-Cheng Li, Shu-Ping Sun, Yu‐Cai Zhang, Jing-Wen DuanMu, Pu‐Gan Lu, Xiaolong Zhang, Fei‐Yue Gao, Yu Yang, Ye-Hua Wang, Peng-Cheng Yu, Shikuo Li, Min‐Rui Gao
Abstract
Electrosynthesis of acetate from carbon monoxide (CO) powered by renewable electricity offers one promising avenue to obtain valuable carbon-based products but undergoes unsatisfied selectivity because of the competing hydrogen evolution reaction. We report here a cerium single atoms (Ce-SAs) modified crystalline-amorphous dual-phase copper (Cu) catalyst, in which Ce SAs reduce the electron density of the dual-phase Cu, lowering the proportion of interfacial K+ ion hydrated water (K·H2O) and thereby decreasing the H* coverage on the catalyst surface. Meanwhile, the electron transfer from dual-phase Cu to Ce SAs yields Cu+ species, which boost the formation of active atop-adsorbed *CO (COatop), improving COatop-COatop coupling kinetics. These together lead to the preferential pathway of ketene intermediate (*CH2-C=O) formation, which then reacts with OH- enriched by pulsed electrolysis to generate acetate. Using this catalyst, we achieve a high Faradaic efficiency of 71.3 ± 2.1% toward acetate and a time-averaged acetate current density of 110.6 ± 2.0 mA cm−2 under a pulsed electrolysis mode. Furthermore, a flow-cell reactor assembled by this catalyst can produce acetate steadily for at least 138 hours with selectivity greater than 60%. Electrosynthesis of acetate from CO using renewable electricity faces low selectivity. Here, the authors report a cerium single atom modulated copper catalyst, where cerium atoms tailor the interfacial water structure, enabling highly selective CO-to-acetate conversion under pulsed electrolysis.