Operando time-resolved X-ray absorption spectroscopy reveals the chemical nature enabling highly selective CO2 reduction
Journal
Nature Communications
Journal Volume
11
Journal Issue
1
Date Issued
2020
Author(s)
Abstract
Copper electrocatalysts have been shown to selectively reduce carbon dioxide to hydrocarbons. Nevertheless, the absence of a systematic study based on time-resolved spectroscopy renders the functional agent—either metallic or oxidative Copper—for the selectivity still undecidable. Herein, we develop an operando seconds-resolved X-ray absorption spectroscopy to uncover the chemical state evolution of working catalysts. An oxide-derived Copper electrocatalyst is employed as a model catalyst to offer scientific insights into the roles metal states serve in carbon dioxide reduction reaction (CO2RR). Using a potential switching approach, the model catalyst can achieve a steady chemical state of half-Cu(0)-and-half-Cu(I) and selectively produce asymmetric C2 products - C2H5OH. Furthermore, a theoretical analysis reveals that a surface composed of Cu-Cu(I) ensembles can have dual carbon monoxide molecules coupled asymmetrically, which potentially enhances the catalyst’s CO2RR product selectivity toward C2 products. Our results offer understandings of the fundamental chemical states and insights to the establishment of selective CO2RR. ? 2020, The Author(s).
Subjects
carbon monoxide; nanotube; atomic absorption spectroscopy; carbon dioxide; catalyst; chemical analysis; electrokinesis; reduction; X-ray spectroscopy; Article; carbon dioxide reduction; chemical reaction kinetics; crystal structure; electrochemical analysis; electron diffraction; elemental analysis; energy dispersive X ray spectroscopy; gas chromatography; hydrogen bond; molecular dynamics; partition coefficient; pH; photothermal therapy; physical chemistry; simulation; static electricity; surface property; thermodynamics; X ray absorption spectroscopy; X ray diffraction
Type
journal article