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采用第一原理计算方法,计算并分析了Cu在Zr掺杂的CeO2(111)表面吸附的吸附能及所形成的Cu/Ce0.75Zr0.25O2(111)界面体系的吸附结构和电子结构.结果表明:1)Cu在Ce0.75Zr0.25O2(111)表面上邻近Zr原子的次层O的顶位吸附最强;2)Zr的掺杂增强了Cu与CeO2衬底的作用;3)Cu的吸附在Ce0.75Zr0.25O2(111)表面的O2p-Ce4f态之间引入了新的间隙态,这些间隙态主要来自于Cu3d与衬底O2p的杂化作用,这是Cu与Ce0.75Zr0.25O2有较强作用的主要原因;4)吸附的Cu被Ce0.75Zr0.25O2氧化为Cuδ+,并伴随着表面Ce4+→Ce3+的转化,该反应可以总结为:Cu/Ce4+→Cuδ+/Ce3+.
Adsorption energy of Cu adsorbed on the CeO2 (111) surface doped with Zr and the structure and electronic structure of the Cu / Ce0.75Zr0.25O2 (111) interface were calculated and analyzed by the first-principles calculation method. Results The results show that: 1) Cu has the strongest adsorption at the top of sublayer O of Zr near the surface of Ce0.75Zr0.25O2 (111); 2) Zr doping enhances the interaction between Cu and CeO2 substrate; 3) New interstitial states have been introduced between the O2p-Ce4f states adsorbed on the surface of Ce0.75Zr0.25O2 (111). These interstitials mainly originate from the hybridization of Cu3d with the substrate O2p, which is a combination of Cu and Ce0.75Zr0.25O2 4) The adsorption of Cu is oxidized by Ce0.75Zr0.25O2 to Cuδ +, accompanied by the conversion of Ce4 + → Ce3 + on the surface. The reaction can be summarized as Cu / Ce4 + → Cuδ + / Ce3 +.