Near ambient-pressure X-ray photoelectron spectroscopy study of CO2 activation and hydrogenation on indium/copper surface

Abstract Indium-based catalysts exhibit excellent performance for CO2 hydrogenation to methanol, yet their nature and chemical evolution under reaction conditions are still elusive, thus hindering an understanding of mechanism. In this work, near ambient-pressure X-ray photoelectron spectroscopy (NAP-XPS) is employed investigate the properties catalytic role indium/copper model conditions. We found that deposition on surface a Cu foil led formation Cu-In alloy, whereas upon exposure, was partially oxidized In2O3-x remains metallic. Due presence In2O3-x, activated In/Cu samples mainly in form carbonate. addition, compared with pure reference, both fraction oxygen vacancies coverage density carbonate were higher samples, indicating promotion effect alloy activation CO2. These results reveal active sites inspire design advanced In-based bimetallic hydrogenation.