The photocatalytic activity of the SnO2/TiO2/PVDF composite membrane in rhodamine B degradation

Abstract

The immobilization of photocatalysts is considered an effective approach to solve the problem of the difficult recycling of powdered nanocatalysts after photocatalytic degradation. In this paper, tin dioxide/titanium dioxide (SnO₂/TiO₂) composite nanoparticles with excellent photodegradation performance and poly(vinylidene fluoride) (PVDF) resin were used as raw materials to prepare composite membranes for the catalytic degradation of rhodamine B (RhB) dye via a non-solvent-induced phase separation method. Specifically, the basic properties of SnO₂/TiO₂ composite nanoparticles were systematically analyzed, the photocatalytic performance of SnO₂/TiO₂/PVDF composite membranes was thoroughly investigated, and the photocatalytic mechanism has been revealed. Experimental results showed that the SnO₂/TiO₂ composite photocatalyst demonstrates a higher photocatalytic activity than the single photocatalyst with the SnO₂/TiO₂ composite comprising Sn/Ti in a molar ratio of 1 : 6, showing the highest photocatalytic performance. After SnO₂/TiO₂ composite particles were used as a kind of raw material for the production of PVDF membrane, the photocatalytic degradation rate of RhB by the SnO₂/TiO₂/PVDF composite membrane was as high as 91.84%. Moreover, ˙OH and h⁺ play a very important role in the whole photocatalytic degradation process. In summary, this paper will provide an effective guidance to improve the photocatalytic degradation of SnO₂/TiO₂/PVDF composite membranes, which will ultimately provide a broad potential application of photocatalysis in the field of water treatment.