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用密度泛函理论B3LYP方法详细研究了Ag_2~-催化CO氧化反应的机理.计算结果表明,O2分子在Ag_2~-和Au_2~-上吸附能相差不大,而CO分子在Ag_2~-上吸附要比在Ag_2~-上弱得多.Ag_2~-催化CO氧化反应共有四条反应途径.最可能反应通道为CO插入Ag2O_2~-中的Ag—O键形成中间体[Ag—AgC(O—O)O]-,然后直接分解形成产物CO2和Ag2O-,或另一分子CO进攻中间体[Ag—AgC(O—O)O]-形成两分子产物CO2和Ag_2~-.在动力学上最难进行的反应通道为经历碳酸根双银中间体,需要克服约0.24eV的能垒.Ag_2~-催化CO氧化反应活性要高于Au_2~-.
The density functional theory B3LYP method was used to investigate the mechanism of Ag_2 ~ - catalyzed CO oxidation. The calculated results show that the adsorption energies of O2 molecules on Ag_2 ~ - and Au_2 ~ ~ are not significantly different, but CO molecules are adsorbed on Ag_2 ~ - Which is much weaker than that of Ag 2 ~ -. There are four reaction pathways for CO 2 oxidation catalyzed by Ag 2 ~ - and the most possible reaction channel is Ag-O bond forming intermediate [Ag-AgC (O-O ) O] -, and then directly decomposed to form CO2 and Ag2O-, or another molecular CO offensive intermediate [Ag-AgC (O-O) O] The refractory reaction channel needed to overcome the energy barrier of about 0.24 eV to undergo the double-silver carbonate intermediate, and the catalytic activity of CO 2 was higher than that of Au 2 ~ -.