The photocatalytic oxidation degradation of NOx in the air with TiO2 thin films

The gas-solid heterogeneous photocatalytic oxidation using TiO2/UV was conducted, and it was found that the degradation efficiency of NOx in air was very high, reaching 97% in the ranges of experimental concentration, Some factors affecting NOx photocatalytic destruction were investigated. The adsorption of NOx on TiO2 thin film surface in the dark, photocatalytic reaction kinetics and mechanism were studied, and some important conclusions were drawn. The product of NOx photocatalysis was detected to be HNO3 by FTIR, The greater part of HNO3 was adsorbed on TiO2 surface, causing catalyst deactivation, but when the catalyst was washed by water, its activity was regenerated as usual, In the end, NOx photocatalytic oxidation experiments were performed under sunlight irradiation, and NOx photocatalytic degradation yields remained high. The results showed that this process has potential applications to the elimination of NOx from the air.