Density functional studies on the thermal decomposition of H2O2 and heterogeneous oxidation of benzene on the Cu surface

Abstract

The related research of volatile organic compounds (VOCs) is of great significance to atmospheric governance. Benzene is extremely harmful to humans and the environment as a representative substance in VOCs. In recent years, H2O2, a highly effective oxidant, has seen usage in flue gas purification. However, the purification efficiency remains limited due to the low utilization rate of hydroxyl radicals (·OH), which are derived from H2O2 decomposition. This research primarily focuses on catalyst selection. Density functional theory (DFT) was employed to investigate the characteristics of H2O2 adsorption and decomposition on Cu-based catalysts, as well as the ineffective consumption reaction of·OH on the Cu surface. Concurrently, the interaction mechanism between benzene and·OH on Cu surface was investigated. The findings demonstrate that Cu-based catalysts can enhance the decomposition of H2O2 molecules, and that H2O2 can dissociate to·OH on the surface. Moreover, these catalysts exert a pronounced inhibitory effect on the ineffective consumption reaction between·OH, H2O2 molecules, and the HO2·. The degradation process of benzene under the influence of·OH was analyzed, and the critical step of the reaction, along with the specifics of the ring-opening reaction, were determined. These reactions mechanisms were elucidated, thereby providing theoretical support for the development of novel catalysts.