Highly selective and stackable electrode design for gaseous CO2 electroreduction to ethylene in a zero-gap configuration

The electrochemical reduction of CO 2 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 CO 2 to ethylene. Using KOH-incorporated Cu nanoparticle (Cu-KOH) as the cathode in a zero-gap electrolyzer , Faradaic efficiency of 78.7% for C 2 products was achieved at a current density of 281 mA cm –2 . Among C 2 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 Cu 2 O and Cu(OH) 2 , which expected a synergistic e…