Study of photocatalytic deactivation mechanism during photooxidation of benzoic acid

The strengthening poisoning of catalysis was used to investigate the process of deactivation of photo-catalyst. The changes of the structure and chemical states of the catalysis have been characterized using TEM, XPS, SPS and IR. The results indicate that the photocatalytic active reduced as well as the increase of SPS during the reaction. The catalyst was deactivated after 20 times. The deactivation catalysis shows aggregation and carbon accumulation, at the same time hydroxide oxygen and the carbon in the -CH₂ and -CH₂OH functional groups increase greatly. The main poisoning compounds are benzoic acid, hydroxide benzoic acid, maleic acid and fumaric.