Co3O4/TiO2 composite photocatalyst: Preparation and synergistic degradation performance of toluene

TiO2 nanobelts and Co3O4/TiO2 catalytic materials were prepared using the hydrothermal method. The catalyst was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, X-ray electron spectroscopy, and fluorescence spectroscopy. At room temperature, with a relative humidity of 50.0%, the total gas flow rate of 1.0 L.min(-1), the space velocity of 1.05x10(4) h(-1), and toluene volume concentration of 25.0 mu L.L-1, two 6 W vacuum ultraviolet lamps were used as light sources to catalyze, degrade, and mineralize toluene. The results show that the prepared catalyst is in the shape of nano-ribbons. The loading of Co3O4 inhibits the recombination of photogenerated electrons and holes and can effectively improve the catalytic performance. The Co3O4/TiO2 with a load of 6.0% Co3O4 has the best catalytic effect. When N-2 was used as a carrier gas, the degradation rate of toluene was only 34.7%. The toluene degradation is mainly due to the photolysis of vacuum ultraviolet light. When air was used as a carrier gas, O-3 was produced. The Co3O4/TiO2 with a load of 6.0% and vacuum ultraviolet synergistically promote toluene degradation. The highest degradation rate of toluene was 91.7% and the mineralization rate was 74.6%. The degradation rate of toluene was 2.6 times that of nitrogen as a carrier gas.