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利用第一性原理计算方法,研究了水在金红石型TiO2(110)表面及<001>阶梯边缘处的吸附.关于水在(110)表面上的吸附,研究表明,对不同的吸附率,水都是以分子模式吸附在表面.关于水在<001>阶梯边缘处的吸附,研究表明,其吸附模式和吸附率有密切的联系.当水的吸附率为一个单层(1ML)时,分子吸附和解离吸附对应的吸附能分别为0.92和0.60eV,分子吸附模式更稳定.当吸附率降为1/2ML时,分子吸附和解离吸附所对应的吸附能分别为0.86和0.84eV,两种吸附模式都可能存在.在表面上,不同吸附模式的吸附能随吸附率变化趋势是一致的.而在<001>阶梯边缘处,对于不同的吸附模式,吸附能随吸附率的变化呈现出不同的变化趋势.这是由在<001>阶梯边缘处低吸附率时解离模式的独特结构引起的.
Adsorption of water on the (110) rutile surface and the <001> edge of the step was studied by first-principles calculations. For the adsorption of water on (110) surface, the results show that for different adsorption rates, water All adsorbed on the surface in molecular mode.According to the adsorption of water on the edge of <001>, the study shows that the adsorption mode is closely related to the adsorption rate.When the adsorption rate of water is a single layer (1ML), the molecular The corresponding adsorption energies of adsorption and dissociative adsorption are 0.92 and 0.60eV, respectively, and the molecular adsorption mode is more stable. When the adsorption rate is reduced to 1 / 2ML, the adsorption energies corresponding to molecular adsorption and dissociative adsorption are 0.86 and 0.84eV, respectively Adsorption modes are all possible. On the surface, the adsorption energies of different adsorption modes are consistent with the change of adsorption rate, while at the edge of <001>, the adsorption energy varies with the adsorption rate for different adsorption modes This is due to the unique structure of the dissociation mode at low adsorption rates at the <001> staircase edge.