Pulsed Electrolysis Promotes CO2 Reduction to Ethanol on Heterostructured Cu2O/Ag Catalysts

• Published in: Small (Weinheim an der Bergstrasse, Germany) Germany), 2024-03, Vol.20 (12), p.e2307637-n/a
• Main Authors: Wu, Xiuju, Li, Xiaotong, Lv, Jiabao, Lv, Xiangzhou, Wu, Angjian, Qi, Zhifu, Wu, Hao Bin
• Format: Article
• Language: English
• Subjects: Carbon dioxide; Catalysts; Copper; Copper oxides; Density functional theory; electrochemical CO2 reduction; Electrolysis; Ethanol; heterostructure; Heterostructures; multi‐carbon products; Nanospheres; pulsed electrolysis; Reduction (electrolytic); Silver; Synergistic effect
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202307637

The electrochemical conversion of carbon dioxide (CO2) into ethanol with high added value has attracted increasing attention. Here, an efficient catalyst with abundant Cu2O/Ag interfaces for ethanol production under pulsed CO2 electrolysis is reported, which is composed of Cu2O hollow nanospheres loaded with Ag nanoparticles (named as se‐Cu2O/Ag). The CO2‐to‐ethanol Faradaic efficiency is prominently improved to 46.3% at a partial current density up to 417 mA cm−2 under pulsed electrolysis conditions in a neutral flow cell, notably outperforming conventional Cu catalysts during static electrolysis. In situ spectroscopy reveals the stabilized Cu+ species of se‐Cu2O/Ag during pulsed electrolysis and the enhanced adsorbed CO intermediate (*CO)coverage on the heterostructured catalyst. Density functional theory (DFT) calculations further confirm that the Cu2O/Ag heterostructure stabilizes the *CO intermediate and promotes the coupling of *CO and adsorbed CH intermediate (*CH). Meanwhile, the stable Cu+ species under pulsed electrolysis favor the hydrogenation of adsorbed HCCOH intermediate (*HCCOH) to adsorbed HCCHOH intermediate (*HCCHOH) on the pathway to ethanol. The synergistic effect between the enhanced generation of *CO on Cu2O/Ag and regenerated Cu+ species under pulsed electrolysis steers the reaction pathway toward ethanol. This work provides some insights into selective ethanol production from CO2 electroreduction via combined catalyst design and non‐steady state electrolysis. An efficient catalyst with abundant Cu2O/Ag interfaces isdeveloped for ethanol production under pulsed CO2 electrolysis. The synergistic effect between the enhanced generation of *CO on Cu2O/Ag and regenerated Cu+ species under pulsed electrolysis steers the reaction pathway toward ethanol.