关键词: 阴离子银团簇, CO氧化反应, 反应机理, 密度泛函理论

The mechanism of -catalyzed CO oxidation was investigated at the level of B3LYP theory. The computational results indicate that the absorption energy of O2 on is close to that of O2 on , while the absorption of CO on is stronger than that of CO on . There are four reaction pathways for CO oxidation catalyzed by . The most feasible pathway is the CO insertion into the Ag—O bond of to produce an intermediate [Ag—AgC(O—O)O]－, and then the intermediate [Ag—AgC(O—O)O]－ decomposes into product CO2 and , or another CO molecule attacks [Ag—AgC(O—O)O]－ to form two CO2 molecules and anion. The most difficult pathway is the di-silver carbonate intermediate pathway, which needs to overcome a total energy barrier of about 0.24 eV. Since for gold, the carbonate-like intermediate pathway requires an activation barrier of 0.61 eV, silver proves to be a better catalyst than gold.

Key words: Ag cluster anion, CO oxidation, mechanism, density functional theory