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

SnS 2 was hybridized with BaTiO 3 to form an efficient and cheap Z-scheme heterojuncted SnS 2 /BaTiO 3 photocatalyst by depositing nanosized SnS 2 on the surface of commercial micro-sized BaTiO 3 . 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 SnS 2 partly covers BaTiO 3 . The photoluminescence (PL) spectra and the electrochemical impedance spectroscopy (EIS) investigation exhibit that the heterojunction SnS 2 /BaTiO 3 has improved the separation and transfer of the photogenerated electron-hole pairs. UV–Vis-DRS and Mott-Schottky measurement give the estimated E g , E CB , and corresponding calculated E VB , which meet the requirements of Z-scheme. The photocatalytic efficiency (degradation is 98% within 20 min) has been greatly enhanced much higher than pure SnS 2 . Free radical trapping experiments indicates that superoxide (•O 2 − ) 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 SnS 2 /BaTiO 3 . This work reveals that Z-scheme composite SnS 2 /BaTiO 3 has prospect in treating organic pollution in waste water.