Carbon foam-supported CdS@ZnO nanocomposites for sustainable water purification and antibacterial applications

Environmental pollution caused by the improper disposal of waste materials, particularly organic dyes from various industries, into water bodies is enormous. It is crucial to comprehensively study photocatalytic materials to effectively degrade dangerous contaminants from water. For this purpose, porous carbon-based materials have drawn great attention because of their unique properties. In this work, a cadmium sulphide-doped zinc oxide integrated carbon foam (CdS@ZnO/CF) nanocomposite has been synthesized by the hydrothermal method. The nanocomposite was characterized by FTIR, XRD, TGA, SEM and EDX. The prepared nanocomposite demonstrated high efficiency in degrading methylene blue (MB) under sunlight irradiation as compared to the individual cadmium sulphide nanoparticles (CdS NPs) and zinc oxide nanoparticle-modified carbon foam (ZnO/CF). CdS@ZnO/CF nanocomposite decreased charge recombination and increased charge separation, which enhanced the photocatalytic degradation activity (up to 93%). Different factors, such as catalyst amount, light exposure duration and concentration of MB, were optimized. After comprehensive experiments, 0.04 g of catalyst, 100 mW/cm2for 80 min of light exposure and 30 ppm concentration of MB was selected as the optimum values for further analysis. The nanocomposite recovered after several cycles and demonstrated a degradation rate of around 85%. In addition, the CdS@ZnO/CF nanocomposite successfully inhibited a famous type of pathogen.