ZnO–SnO 2 –Sn nanocomposite as photocatalyst in ultraviolet and visible light

By combining ZnO with SnO2, it is possible to obtain a photocatalyst with an extended lifetime and increased activity range in both ultraviolet and visible light. The paper presents the synthesis of ZnO–SnO2–Sn nanocomposite. The morphology and structure of the samples were characterized by XRD, FTIR, SEM–EDS and TEM–EDX analysis. The results showed that the synthesised nanocomposites consisted of hexagonal ZnO, cubic SnO2 and Sn nanoparticles. The results revealed that the highest removal efficiency (15.0%) of rhodamine B under visible light was achieved with ZnO–SnO2–Sn consisting of 10% of SnO2 and 5% of Sn, whereas the highest removal efficiency of methylene blue (95.6%) under UV light was achieved with ZnO–SnO2–Sn consisting of 10% of SnO2 and 1% of Sn. The presence of tin nanoparticles enhanced the photocatalytic properties directed towards visible light. The degradation of MB by ZnO–SnO2–Sn remained above 80% even in the 5th cycle, while under visible light during photodegradation the RB removal efficiency decreased from 20 to 14%.