Investigation of Formaldehyde Adsorption on ZnO(0001) Surface by Density Functional Theory
Dazhi Chen, Yuxuan Liu, Yong Yuan
Abstract
Abstract The interaction between formaldehyde and ZnO (0001) was investigated by density functional theory (DFT) to evaluate the detection of formaldehyde. The results demonstrated that the nature adsorption interactions between formaldehyde molecule and ZnO was physical, with the binding distance of 2.081 Å, the binding energy of 0.496 eV and the total charge transfer of 0.089 e. Formaldehyde molecule played the role of electron acceptor in the adsorption process and trapped electrons from the ZnO surface. After formaldehyde adsorption, the impurity levels appeared and the band gap tended to narrow compared with that before formaldehyde adsorption. When there were more formaldehyde molecules in space, they were preferentially adsorbed on the ZnO surface. It is expected that the results obtained in this study could provide a useful theoretical guidance for the investigation of ZnO films interface bonding and design of formaldehyde sensing devices.