Theoretical mechanistic study of CO catalytic oxidation by O<inf>2</inf> on an ultra-small 13-atom bimetallic Ag<inf>7</inf>Au<inf>6</inf> cluster

• Main Authors: Preeyaporn Poldorn, Yutthana Wongnongwa, Supawadee Namuangruk, Nawee Kungwan, Vladimir B. Golovko, Burapat Inceesungvorn, Siriporn Jungsuttiwong
• Format: Journal
• Published: 2020
• Subjects: Chemical Engineering
• Online Access: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85081200343&origin=inward; http://cmuir.cmu.ac.th/jspui/handle/6653943832/68281
• Institution: Chiang Mai University

© 2020 Elsevier B.V. We report an advanced configurational sampling method that uses density functional theory (DFT) to design a highly active catalyst for conversion of CO into less-harmful products, under ambient conditions. The reaction pathway for CO oxidation by O2 on ultra-small 13-Atom bimetallic Ag7Au6 cluster has two possible mechanisms, namely, stepwise adsorption and co-adsorption. The rate-determining step involving with CO[sbnd]O association via a co-adsorption process shows a significantly small barrier of 0.21 eV. Furthermore, microkinetic simulation results suggest that CO oxidation rates and the optimal temperature for CO oxidation exhibit both greater performances for the co-adsorption pathway, compared to that for a stepwise-adsorption mechanism. Our new proposed mechanism suggests that the bimetallic Ag7Au6 catalyst is active for CO oxidation at room temperatures. Thus, it has potential application as a highly-active catalyst for conversion of carbon monoxide into less toxic CO2.