Simple synthesis of WO3-Au composite and their improved photothermal synergistic catalytic performance for cyclohexane oxidation

Abstract

Partial oxidation of cyclohexane (CHA) to KA oil (cyclohexanone (-one) and cyclohexanol (-ol)) with dry air is one of the most important industrial process. Despite great efforts have made in developing new catalysts, industrial processes are still limited by low conversion and selectivity with harsh condition. Here we report a significantly improved cyclohexane conversion and KA oil selectivity under solar light irradiation by anew photothermal synergistic catalyst, which was prepared by loading Au nanoparticles (Au NPs) onto WO3 nanosheets (WO3 NSs) with simple ultrasonic method. A high conversion of 9.0% and a high selectivity of 99.0% are acquired by WO3 nanosheets-Au nanoparticles (WO3-Au) composite under dry air, which are much higher than the simple sum of photocatalysis and thermal catalysis. The significantly improved catalytic properties of cyclohexane oxidation by the WO3-Au composite are mainly attributed to the improved light absorption, the effective charge separation and the synergistic effect of photocatalysis and thermal catalysis. The photothermal synergy to improve catalytic activity may be widely used in green industrial catalytic processes.