Highly selective and stackable electrode design for gaseous CO2 electroreduction to ethylene in a zero-gap configuration. (June 2021)

• Record Type: Journal Article
• Authors: Lee, Woong Hee; Lim, Chulwan; Lee, Si Young; Chae, Keun Hwa; Choi, Chang Hyuck; Lee, Ung; Min, Byoung Koun; Hwang, Yun Jeong; Oh, Hyung-Suk
• Is Part Of: Nano energy. Volume 84(2021)
• Publication Date: 2021-06
• Subjects: Zero-gap electrolyzer -- CO2 reduction reaction (CO2RR) -- Ethylene -- KOH incorporated Cu -- Scaling and stacking up system; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2021.105859
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: The electrochemical reduction of CO2 to ethylene has the potential to reduce greenhouse gas emissions while producing commodity chemicals for plastics; however, a scalable and feasible system for this remains a challenge. Herein, we report an efficient and stackable electrode design for the electrolysis of CO2 to ethylene. Using KOH-incorporated Cu nanoparticle (Cu-KOH) as the cathode in a zero-gap electrolyzer, Faradaic efficiency of 78.7% for C2 products was achieved at a current density of 281 mA cm –2 . Among C2 products, ethylene with a 54.5% FE was dominant product. For mass production, three membrane electrode assemblies (MEAs) were stacked and operated. Operando X-ray absorption spectroscopy under the zero-gap electrolyzer suggested mainly metallic Cu state with some persistent oxide-derived Cu species in Cu-KOH, including Cu2 O and Cu(OH)2, which expected a synergistic effect for the conversion of CO2 to C2 H4 . Our findings provide a new strategy for converting CO2 to C2 H4, which is expected to accelerate the commercialization of high-value chemical production through electrochemical CO2 reduction. Graphical Abstract: KOH incorporated Cu electrode in zero-gap electrolyzer achieved a current density of 281 mA cm –2 with a Faraday efficiency of 54.5% toward C2 H4 . Operando X-ray Absorption Spectroscopy reveals that the presence of Cu2 O and Cu(OH)2 species during CO2 RR condition exhibit synergistic effect to improve selectivity and kinetics for CO2 conversion to C2 H4 . Furthermore, 3-cell stack operation result suggests the possibility of industrial development. ga1 Highlights: KOH incorporated Cu in zero-gap electrolyzer achieved a current density of 281 mA cm –2 with a FE of 54.5% toward C2 H4 . Operando X-ray Absorption Spectroscopy suggests the presence of Cu2 O and Cu(OH)2 species during CO2 RR condition. Synergistic effect of Cu2 O and Cu(OH)2 species improve selectivity and kinetics for CO2 RR to C2 H4 . C2 H4 FE of 50% at a current density of 200 mA cm 2 for 6 h was achieved in a 3-cell stack. 3-cell stack operation result suggests the possibility of industrial development.