Barium stannate/graphitic carbon nitride S-scheme heterojunction as an efficient photocatalyst for removal of toxic coloring agents under visible light

Photocatalyst heterojunctions are crucial for efficient long-term carrier separation and for increasing the photocatalytic efficiency of single catalysts. A simple and low-cost method of fabricating barium stannate (BaSnO3, ZSO) is described in this paper, as well as the co-precipitation process with ultrasonic assistance that is used to produce barium stannate/graphitic carbon nitride nanocomposites (BaSnO3/g-C3N4, BSO/CN) with varying amounts of BSO. Various analytical techniques were used to evaluate the purity, morphology, and structure of the products, including XRD, FTIR, EDS, FESEM, TEM, BET, DRS, and PL. CN lowered the bandgap of BSO, allowing it to be used in the visible spectrum according to DRS data. An evaluation of BSO, CN, and several BSO/CN nanocomposites was conducted to determine their ability to degrade erythrosine (ER) and eriochrome black T (EBT). Results showed that the efficiency of the dye was affected by several factors, including the concentration of BSO, the quantity of catalyst, and the dye concentration. In a BSO/CN nanocomposite containing 0.1 g of BSO and 60 mg of ZSO/CN (0.1:1), 88.4 % of ER was degraded. As revealed by the scavenger experiments, superoxide radicals exhibit remarkable properties in photoreactions. It appears that higher levels of competence (88.4 %) were associated with the highest rate constant (k = 0.0256 min−1) according to the kinetics survey.