promoting visible-light degradation of toluene over a simple constructed tio2/pd nanocomposite as photocatalytic coating air purification filter

A series of air filters based on the tio2/pd nanophotocatalyst were prepared using the colloid solution method in the presence of polyvinyl alcohol (pva) as a surfactant. the morphology, surface area, and visible light adsorption properties, were investigated using fesem, bet, and drs analysis. as a result, the nitrogen adsorption-desorption isotherms of the catalysts showed that the n2 adsorption ability of the resulted nanophotocatalysts (1.5 wt.% of pva) was better than the tio2 and other catalyst samples with more surface area. the photocatalytic activity of the nanophotcatalyst filter was investigated in the experiments of the photocatalytic degradation of toluene in a gaseous phase under visible light illumination. among all the filters, the 10 wt.% nanophotcaotalyst filter demonstrated the highest photocatalytic ability to decompose toluene. the photocatalytic efficiency of the nanophotocatalyst with the 1.5 wt.% of pva was remarkably enhanced by toluene removal. the led lamp-60 w achieved the highest photocatalytic activity. the enhanced photodegradation of toluene is possibly due to the improved adsorption ability and the enhanced electron-hole pairs separation due to the presence of pd nanoparticles on the surface of tio2 nanocatalyst and the electron transfer between the conduction band/defect level and pd nanoparticles.