Visible light assisted degradation of Rhodamin B by reusable S-doped ZnO thin film photocatalyst

The use of zinc oxide-based photocatalysts has been extensively conducted to breakdown harmful pollutants in wastewater treatment. Recently, ZnO doped non-metal can improve photocatalytic activity by reducing charge carrier recombination. Here, S-doped ZnO thin films, with a sulfur dopant of 1 and 5% molar, were synthesized by a seed-mediated hydrothermal process. The enhancement in crystal structure and morphology were noted with the presence of sulfur in the ZnO system. The photocatalytic test shows that the presence of sulfur enhances Rhodamine B (RhB) degradation efficiency up to 92% with reaction rates of 1.67 × 10−2 min−1 under visible light. The S-doped ZnO thin film is potentially applied as a stable photocatalyst for wastewater purification, with a noted photocatalytic efficiency of 75% after repeated use.