Preparation and study of photocatalytic performance of a novel Z-scheme heterostructured SnS2/BaTiO3 composite

SnS2 was hybridized with BaTiO3 to form an efficient and cheap Z-scheme heterojuncted SnS2/BaTiO3 photocatalyst by depositing nanosized SnS2 on the surface of commercial micro-sized BaTiO3. Multiple characterization techniques have been employed to study the as-prepared samples. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) results reveal that SnS2 partly covers BaTiO3. The photoluminescence (PL) spectra and the electrochemical impedance spectroscopy (EIS) investigation exhibit that the heterojunction SnS2/BaTiO3 has improved the separation and transfer of the photogenerated electron-hole pairs. UV–Vis-DRS and Mott-Schottky measurement give the estimated Eg, ECB, and corresponding calculated EVB, which meet the requirements of Z-scheme. The photocatalytic efficiency (degradation is 98% within 20 min) has been greatly enhanced much higher than pure SnS2. Free radical trapping experiments indicates that superoxide (•O2−) is the dominant active species of the reaction system. The improved photocatalytic performance, as well as the free radical trapping experiments support the Z-scheme mechanism for composite photocatalyst SnS2/BaTiO3. This work reveals that Z-scheme composite SnS2/BaTiO3 has prospect in treating organic pollution in waste water. •Novel Z-scheme photocatalyst SnS2/BaTiO3.•Superior photocatalytic performance: It is only 0.03 g SnS2/BaTiO3 composite that can degrade 100 mL MO to 98% in 20 min.•Abundant-earth elements: the constituent elements are abundant in the crust and are easy to obtain.•Facile preparation method.