Adsorption and conversion of small gases on TiO2 nanoparticles and surfaces of modified TiO2

Abstract

Adsorptions of small gases and their reactions on modified anatase TiO2 (001) as ZnOSL supported on anatase TiO2 (001), (ZnOSL/TiO2), and Mn–doped TiO2 (001) surfaces have been studied by density functional theory (DFT) method. The calculation models relied on both of clusters and periodic boundary conditions (PBCs). It was found that Ti5C and O2c sites on anatase TiO2 (001) are active for ZnOSL supporting. The conversion of carbon monoxide by oxygen forming carbon dioxide gas over the ZnOSL/TiO2 composite was studied. Moreover, ZnOSL, transition metals, and non–metals doped–ZnOSL clusters have studied to understand the properties of their surfaces. Resulting from the study of small gases on the Sc–ZnOSL, the most stable adsorption configuration is SO2 adsorption. The most decreasing of energy gap for N2O bridge–structured adsorption on Sc–ZnOSL was found. The Sc–ZnOSL used as N2O or SO2 sensing material was suggested. For the system of Mn–doped anatase (001) surface, Mn–doped anatase (001) surface enhances the activity of O2 pre–adsorption and CO adsorption for CO to CO2 conversion. Therefore, the results indicate that modified anatase (001) surface can be used for the conversion of carbon monoxide by oxygen gas forming carbon dioxide gas reaction.