u-Zn-Al三元模型催化剂的制备及其氧化还原性能的研究

he Cu/Al2O3/ZnO(0001)-Zn ternary model catalysts were prepared and characterized, as well as the growth of binary model catalysts: Al2O3/ZnO(0001)-Zn and Cu/ZnO(0001)-Zn. The Al2O3/ZnO was prepared by depositing Al onto ZnO surface in O2 atmosphere at 523 K, and Cu/ZnO was prepared by depositing Cu onto ZnO surface at room temperature. It was found that Al2O3 grew on the ZnO(0001)-Zn surface by a layer-by-layer model, while Cu formed two-dimensional islands only at low coverage and three dimensional clusters at high coverage. Comparing to the Cu/ZnO binary model catalyst, the addition of Al2O3 obviously slowed down the reduction of Cu/Al2O3/ZnO by H2，which may help to stabilize the surface Cu+.