Polyvinyl alcohol–titanyl hybrid films: synthesis, characterization, and photocatalytic degradation of rhodamine B under artificial and solar light

Finding new, effective photocatalysts for the degradation of organic pollutants is a pressing issue in water treatment. Oxide photocatalysts are difficult to synthesize and impractical to use because they are most effective in the form of suspensions, sols, or nanoscale powders. This article demonstrates the photocatalytic ability of a hybrid polyvinyl alcohol-titanyl film photocatalyst to degrade Rhodamine B and formaldehyde. This hybrid material is an easily synthesized alternative to oxide photocatalysts that can be used to photodegrade organic pollutants. 99.8 % of Rhodamine B is degraded in 90 min with a catalyst-to-solution ratio of 1:100 for a 0.05 mM Rhodamine B solution. The film photocatalyst is transparent and colorless, with a band gap of 3.39 eV and an adsorption edge at 354 nm, corresponding to a forbidden direct transition. After irradiation, the photocatalyst's color changed to blue, and new photodegradation activity peaks were registered at 400 and 500 nm. The reversible color change of the photocatalyst enhances light absorption and promotes the effective separation of electron-hole pairs. Based on data from the Scavenger study and TOC measurements, a mechanism for the photodegradation of Rhodamine B on a hybrid polyvinyl alcohol-titanyl photocatalyst was proposed. The structure of the hybrid photocatalyst was characterized using XPS and IR spectroscopy, and the distribution of titanium in polymeric matrix was analyzed by SEM combined with EDX. This work demonstrates the potential of the synthesized polyvinyl alcohol-titanyl hybrid photocatalyst for the efficient photodegradation of organic pollutants.