The visible light photocatalytic degradation of ethylene using a polyvinyl alcohol film loaded with Ag2O-TiO2-Bi2WO6 heterojunction microspheres

In this study, Ag2O-TiO2-Bi2WO6(ATB) heterojunction microsphere photocatalyst was synthesized by hydro thermal and surface deposition method. ATB was loaded onto the surface and interior of polyvinyl alcohol (PVA) films to construct a novel ATB/PVA composite film with photocatalytic degradation performance of ethylene by internal doping and surface loading method. The ATB microspheres and ATB/PVA composite films were characterized, and the photodegradation effect and mechanism of ethylene by ATB/PVA composite films was investigated. The results showed that ATB had the best ethylene degradation effect, and the reaction rate constant K' value was 6.0722 x 10(-4) min(-1), which was 11.79, 2.71 and 1.48 times than that of TiO2, Bi2WO6 and TiO2/Bi2WO6(TB), respectively. The improvement of photocatalytic activity was mainly attributed to the addition of Ag2O, which enhanced the visible light absorption performance and reduced the band gap of ATB. The formation of ternary heterostructures promoted the separation and transfer efficiency of photogenerated carriers. When the internal doping amount of ATB was 3 wt% and the surface loading amount was 1.5 wt%, the ATB microspheres were well dispersed inside and on the surface of PVA film, and the ATB/PVA composite film had the best ethylene degradation performance with K 'value of 6.8107 x 10(-4) min(-1), which was increased by 12.16% compared with the pure internal doping film.

Automated summary

This study successfully synthesized Ag2O-TiO2-Bi2WO6 (ATB) heterojunction microsphere photocatalyst and loaded it onto PVA films to construct ATB/PVA composite films. The results showed that ATB had excellent ethylene degradation performance, which was attributed to the addition of Ag2O and the formation of ternary heterostructures.