IR spectroscopic characterization of the co-adsorption of CO2 and H2 onto cationic Cun+ clusters. Issue 47 (28th October 2021)

• Record Type: Journal Article
• Authors: Lushchikova, Olga V.; Szalay, Máté; Tahmasbi, Hossein; Juurlink, Ludo B. F.; Meyer, Jörg; Höltzl, Tibor; Bakker, Joost M.
• Is Part Of: Physical chemistry chemical physics. Volume 23:Issue 47(2021)
• Page Start: 26661
• Page End: 26673
• Publication Date: 2021-10-28
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d1cp03119h
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : To understand elementary reaction steps in the hydrogenation of CO2 over copper-based catalysts, we experimentally study the adsorption of CO2 and H2 onto cationic Cu n + ( n = 4–7) clusters. Abstract : To understand elementary reaction steps in the hydrogenation of CO2 over copper-based catalysts, we experimentally study the adsorption of CO2 and H2 onto cationic Cu n + clusters. For this, we react Cu n + clusters formed by laser ablation with a mixture of H2 and CO2 in a flow tube-type reaction channel and characterize the products formed by IR multiple-photon dissociation spectroscopy employing the IR free-electron laser FELICE. We analyze the spectra by comparing them to literature spectra of Cu n + clusters reacted with H2 and with new spectra of Cu n + clusters reacted with CO2 . The latter indicate that CO2 is physisorbed in an end-on configuration when reacted with the clusters alone. Although the spectra for the co-adsorption products evidence H2 dissociation, no signs for CO2 activation or reduction are observed. This lack of reactivity for CO2 is rationalized by density functional theory calculations, which indicate that CO2 dissociation is hindered by a large reaction barrier. CO2 reduction to formate should energetically be possible, but the lack of formate observation is attributed to kinetic hindering.