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在分子尺度上介绍了Au/TiO_2(110)模型催化剂表面和单晶Au表面CO氧化反应机理和活性位、以及H_2O的作用.在低温(<320 K),H_2O起着促进CO氧化的作用,CO氧化的活性位位于金纳米颗粒与TiO_2载体界面(Au~(δ+)O~(δ–)––Ti)的周边.O_2和H_2O在金纳米颗粒与Ti O_2载体界面边缘处反应形成OOH,而形成的OOH使O–O键活化,随后OOH与CO反应生成CO_2.300K时CO_2的形成速率受限于O_2压力与该反应机理相印证.相反,在高温(>320 K)下,因暴露于CO中而导致催化剂表面重组,在表面形成低配位金原子.低配位的金原子吸附O_2,随后O_2解离,并在金属金表面氧化CO.
The CO oxidation reaction mechanism and active sites on the surface of Au / TiO_2 (110) catalyst and the surface of single crystal Au were also described on the molecular scale. The effect of H_2O on H_2O was also discussed. H_2O played the role of promoting CO oxidation at low temperature (<320 K) The active site of CO oxidation is located at the periphery of the interface between gold nanoparticle and TiO 2 support (Au δ (δ) O δ -Ti) .O_2 and H_2O react at the edge of interface between Au nanoparticles and Ti O_2 support to form OOH , While the formed OOH activates the O-O bond, followed by the reaction between OOH and CO to form CO 2. The formation rate of CO 2 at 300K is limited by the O 2 pressure and the reaction mechanism confirms that, at high temperature (> 320 K) Exposure to CO resulted in the recombination of the catalyst surface and the formation of low-coordination gold atoms on the surface. The low-coordination gold atoms adsorbed O 2 and subsequently O 2 dissociated and oxidized CO on the gold metal surface.