AVS 61st International Symposium & Exhibition
    Surface Science Monday Sessions
       Session SS+EN-MoA

Paper SS+EN-MoA7
Growth and Characterization of Ultrathin ZnO Layers on Au(111) – STM Study of Growth Mode and Adsorption of Water

Monday, November 10, 2014, 4:00 pm, Room 309

Session: Metals, Alloys and Oxides: Structure, Reactivity & Catalysis
Presenter: Junseok Lee, National Energy Technology Laboratory
Authors: J. Lee, National Energy Technology Laboratory
X. Deng, National Energy Technology Laboratory
D.C. Sorescu, National Energy Technology Laboratory
Correspondent: Click to Email
Zinc oxide is an important material in the low-temperature synthesis of methanol. In this study, the growth mode of ZnO ultrathin films has been studied on the Au(111) surface using scanning tunneling microscopy (STM). The ultrathin ZnO layers have been found to grow by forming islands on Au(111). Different growth conditions during reactive deposition resulted in ZnO islands whose thickness ranging from one to four layers. The STM results and the density functional theory (DFT) calculation have been used to model the observed phenomena. STM results indicate that the brightness of the Moire pattern of the ZnO layer on Au(111) surface is significantly modulated by the adsorption of water molecule at the positive tip bias. Various water adsorption sites have been identified in the STM results after annealing the sample to various temperatures that correspond to temperature programmed desorption (TPD) peaks. The DFT calculation results provide the most stable configurations of water molecules at each adsorption site.