Ultrastable photodegradation of formaldehyde under fluorescent lamp irradiation by anti-reflection structure SnS2/TiO2 composite

In this work, mesoporous titanium dioxide sphere Mp-TiO2/SnS2 composites have been synthesized for the photodegradation of formaldehyde with fluorescent lamp. SnS2 nanosheets/nanoparticles were deposited on the surface of Mp-TiO2 sphere uniformly through an in-situ method. The morphology of SnS2 can be modulated through adjusting the Sn/Ti molar ratio. SnS2 nanosheet turned into nanoparticle when the Sn/Ti molar ratio changed from 0.05 and 0.10 to 0.15 and 0.20. The physical and chemical properties of as-prepared composite catalysts were thoroughly studied by X-ray diffraction (XRD), Raman, scanning electron microscope (SEM), Brunauer Emmett Teller (BET), energy-dispersive X-ray spectroscopy (EDS), photoluminescence (PL) and UV-vis spectrophotometer. The photocatalytic performance of Mp-TiO2/SnS2 in the degradation of HCHO was assessed in a smog chamber with the irradiation of fluorescent light. A degradation efficiency of about 63% was achieved when the molar ratio of SnS2/TiO2 was 0.10. Through extending the light absorption range and hindering the recombination of photo-generated electron-hole pairs, the combination with SnS2 enabled the fabrication of hybrid photocatalysts with high photocatalytic activity and long-term stability.