Enhanced visible-light photocatalytic degradation of hazardous organic dyes by the MCM-41 supported Bi2S3/CdS heterostructure

Abstract

Water contamination by hazardous organic dyes raises major health and environmental issues, necessitating the development of effective and long-lasting treatment technologies. In this study, the Bi₂S₃/CdS (BS/CdS) heterostructure supported on mesoporous MCM-41 was fabricated via a facile and cost-effective hydrothermal method. The combination of CdS and Bi₂S₃ effectively tunes the band gap to the desired value, enabling the solar-driven photocatalysis. Moreover, the incorporation of MCM-41 with the Bi₂S₃/CdS composite enhances the surface area, structural stability, and charge carrier separation of the photocatalyst. Several electrochemical tests, including chronoamperometry (I–t), electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV), and Mott–Schottky analysis, were utilized to further validate the high capacity for charge transfer and the reduction of electron–hole recombination. Under visible light irradiation, the photodegradation of rhodamine B (RhB) dye was employed to assess the photocatalytic activity of the prepared samples. Among all samples, 10 MCM@BS/CdS exhibited the highest visible light degradation performance of 99.3%.