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分别以清洁及氧修饰Cu（100）表面作为金属态铜和部分氧化态铜的表面模拟，用键级守恒-Morse势法研究了两种表面上CO2加氢制甲醇反应的能量学．计算结果表明：在两种表面上，CO2加氢制甲醇反应的优势反应途径均为“CO2，s→HCOOs→H2COs→CH3Os→CH3OHs”；与清洁铜表面上的相应基元步骤相比，在CU（100）-p（2X2）O表面上甲醇合成反应各基元步骤具有更低的活化能；HCOOs是合碳产物CH3OH、CO共同的前驱中间体，甲醇选择性由HCOOs的氢解反应与其解离生成COs及OHs竞争反应的相对速率决定；在清洁铜表面上，HCOOs的氢解反应与其解离生成COs及OHs竞争反应具有相似的活化能，而在氧修饰铜表面上，前者的活化能显著低于后者．因此，从反应能量学角度看，甲醇合成反应在部分氧化态铜表面上比在金属态铜表面上更有利．
The energetics of the two reactions of CO2 hydrogenation to methanol were studied by the surface-directed simulation of clean and oxygen-modified Cu (100) surfaces as metallic copper and partially oxidized copper, respectively. The calculated results show that on both surfaces, the dominant reaction pathways for methanol reactivity by CO2 hydrogenation are “CO2, s → HCOOs → H2COs → CH3Os → CH3OHs”. Compared with the corresponding elementary steps on the surface of clean copper, HCOOs are the common precursors to the co-products of CH3OH and CO, and the selectivity of methanol is determined by the hydrogenolysis reaction of HCOOs with The relative rates of dissociation of COs and OHs were determined. On the clean copper surface, the hydrogenolysis reaction of HCOOs had a similar activation energy with the dissociation of COs and OHs. On the surface of oxygen-modified copper, the activation of the former Can be significantly lower than the latter. Therefore, from the point of view of reaction energetics, the methanol synthesis reaction is more favorable on the partially oxidized copper surface than on the metallic copper surface.