A Novel Bromeliad Flower-Like Visible-Light Photocatalyst of CdS and Its Photocatalytic Activity for Industrial Dye Treatment Towards Environmental Remediation: Active Species, Mechanism, and Stability

In this study, a new bromeliad flower-like CdS photocatalyst was prepared using an easy hydrothermal technique based on dye adsorption for the photocatalytic destruction of organic contaminants under visible-light irradiation. The synthesized photocatalyst was characterized using a variety of analytical methods. The x-ray diffraction (XRD) pattern revealed that the synthesized CdS photocatalyst exhibited a hexagonal phase. Field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) confirmed the novel bromeliad flower-like morphology of the synthesized CdS. High-resolution (HR)-TEM images revealed the interior structure and the (002) plane lattice spacing of the wurtzite structure of the photocatalyst. The specific surface area was found to be 33.96 m 2 g −1 . Ultraviolet–visible–near-infrared (UV-Vis NIR) spectroscopy revealed a greater photocatalytic response in the visible region. The visible-light photodegradation of crystal violet (CV), rhodamine B (RhB), and methylene blue (MB) dye in the presence of the photocatalyst displayed high decolorization efficiency, with 96%, 96%, and 88% degradation of CV, RhB, and MB at 35 min, 115 min, and 145 min, respectively, under the same conditions. The photocatalytic degradation of CV dye was better than the degradation of RhB and MB dyes. Based on these results, a plausible photocatalytic mechanism is proposed for the bromeliad flower-like CdS photocatalyst. Graphical Abstract