Application of CdS QDs incorporated in magnetized powder activated carbon for degradation of some dyes: Photodegradation process and comprehensive catalytic and spectroscopic studies

Abstract

In this study, a feasible, straightforward method was proposed for degradation of organic pollutants in wastewater. Nano-photocatalysts were fabricated by deposition of CdS quantum dots on magnetized powder activated carbon (MPAC) through impregnation technique. To thoroughly characterize the synthesized materials, i.e. MPAC, CdS and CdS@MPAC, several techniques have been employed, including X-Ray diffractometer (XRD), field emission scanning electron microscopy (FE-SEM), UV–vis, Fourier transform infrared (FT-IR), and vibrating sample magnetometer (VSM). The photocatalytic activity of CdS@MPAC was investigated by photodegradation of organic compounds such as methylene blue (MB), crystal violet (CV) and ethyl green (EG) under two different solar irradiation sources, namely fluorescent lamp and natural sun light. In addition, the potential influential parameters on the degradation of organic compounds such as pH, irradiation time, agitation rate and amount of the photocatalyst were examined on degradation efficiencies of dyes. Results specified that degradation process was carried out with such a high efficiency that near 99% of the dyes were degraded using CdS@MPAC under irradiation of fluorescent lamp (260 mg L−1 of photocatalyst, pH 7.0, 600 rpm and 35 °C). Degraded products were analyzed with different techniques such as UV–vis spectroscopy, 1H NMR, 13C NMR and GC–MS. Finally, CdS@MPAC was successfully used for photodegradation of the dyes in real samples under illumination of natural sun light.