Ba和Sr原子在ZnO(0001)表面吸附的密度泛函理论研究

我们采用密度泛函理论下的平面波赝势方法研究Ba和Sr原子在ZnO(0001)表面的吸附结构和性质，仔细研究了三个吸附位（T4, H3 and Top）。发现Ba和Sr吸附在表面的H3和T4位时，他们之间的结合能相差很小，且这两种金属更易于吸附在表面的T4位，我们把计算的结果与贵金属在ZnO(0001)表面的吸附行为及前人的实验结果进行了比较，理论上发现Ag和Au易于吸附在ZnO(0001)表面的H3位，而实验上观察到即使在很小吸附比的条件下ZnO(0001)表面上也能形成Cu的团簇结构，这主要是由于Cu和ZnO(0001)表面衬底强的相互作用所致。

Theoretical Study of Adsorption of Ba and Sr atoms on wurtzite ZnO(0001) surface with DFT approach

Density functional calculations with the plane-wave pseudopotential method have been performed to investigate the structures and properties of the adsorption of Ba and Sr atoms on ZnO(0001) surface. Three adsorption sites (T4, H3 and Top) have been explored carefully. The difference of binding energies is small between the adsorption models on H3 and T4 sites of the Ba- or Sr-adsorbed surfaces. Both the metal atoms prefer to be absorbed on T4 sites of the surface. The results were compared with those of the noble metal atoms-adsorbed ZnO(0001) surfaces and available experiments. In theory, some noble metals such as Ag and Au atoms prefer to be adsorbed H3 sites of ZnO(0001) surfaces and Cu clusters can be formed experimentally resulting from strong interactions between Cu and the ZnO(0001) substrate even for very small coverage.