In situ preparation of a recyclable hydrogel-based photocatalyst and its application in sunlight-promoted photodegradation of eosin Y

A hydrogel-based photocatalyst is synthesized by the construction of a hydrogel skeleton using common monomers and subsequent in situ generation of Zn–Cu–S photocatalyst particles. The photocatalytic degradation performance of the hydrogel-based photocatalyst is systematically studied, and the photocatalyst exhibits good removal ability for eosin Y. The composite photocatalyst shows high efficiency at low loading, with a removal rate of up to >98% in 3 hours under sunlight irradiation, without the need for a preliminary dark adsorption process. High removal efficiency was observed, remaining above 95% even after 10 recycling runs, demonstrating the excellent stability of the composite photocatalyst. We thus provide a facile method to construct hydrogel-based photocatalysts that show high application potential in the photocatalytic removal of eosin Y.