Synergistic effects of Au and PdOx on the solar-assisted catalytic ozonation of VOCs

Abstract

Solar-assisted catalytic ozonation is a low-consumption and high-efficiency strategy for removing low-concentration VOCs. The photothermal conversion capability and catalytic ozonation activity of the catalyst need to be improved with a low load of noble metals. In this work, we coloaded Au and Pd on CeO₂ to enhance photo-assisted catalytic ozonation performance through their synergistic effect. X-ray photoelectron spectroscopy and temperature-programmed desorption experiments were performed to analyze the effects of Au and Pd. Results show that the synergy factor of full-spectrum light and ozone for PdO_x–Au–CeO₂ was 8.94, 1.11, and 1.28 times higher than those for Au–CeO₂ and PdO₂–CeO₂, respectively. Au loading significantly enhanced light absorption and photothermal-conversion capability. The coloading of Au and PdO_x increased surface Ce³⁺–OH₂⁺ and reduced the difficulty of surface oxygen vacancy formation, thereby promoting ozone utilization for toluene degradation. This work proposed a method of efficiently utilizing solar energy for VOC control.