CaSnO3 coupled g-C3N4 S-scheme heterostructure photocatalyst for efficient pollutant degradation.

The perovskite CaSnO 3 /g-C 3 N 4 heterostructure nanocomposite was successfully prepared via facile solid-state route. The properties of morphology, structural, optical, functional, elemental, surface, electrochemical and photocatalytic performances were investigated. The synthesised CaSnO 3 (CS) nanoparticles were grafted on the g-C 3 N 4 nanosheets and their photocatalytic performance were determined. The introduction of g-C 3 N 4 possesses solid-solid intimately contacted interfaces with CS that provides more transport paths and effectively improve the separation of photogenerated electrons and holes (e−/h+). Thus, the formation of CaSnO 3 /g-C 3 N 4 (CGN) heterostructures exhibits with tunable optical bandgap and suppresses the charge recombination process that leads to improve the photocatalytic efficiency. Compared with bare CS the CGN photocatalyst achieves 95% of degradation efficiency over methylene blue (MB) dye in 120 min of UV–visible light irradiation. The possible photocatalytic degradation mechanism was discussed. Furthermore, the CGN photocatalyst has been utilized for 4 repeated runs of experiments which shows good stability and reusability after the degradation experiments. [Display omitted] • Perovskite CaSnO 3 /g-C 3 N 4 photocatalyst was successfully prepared via facile method. • Maximum degradation efficiency was attained up to 95% after 120 min of irradiation. • Superoxide radicals are the key active species in the MB dye degradation process. • CGN photocatalyst has been highly stable and reusability after 4 recycles. [ABSTRACT FROM AUTHOR]