DOI: https://doi.org/10.55373/mjchem.v26i4.39

Keywords: Safranin; photocatalysis; wastewater; LED light; degradation; ZnO/CdS photocatalyst

Abstract

A ZnO/CdS photocatalyst was prepared using the sol-gel synthesis technique. The performance of the photocatalyst was evaluated using a Safranin solution assisted by 21-Watt LED visible light. The ZnO/CdS was characterized by field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and ultraviolet-visible-near-Infrared spectrophotometry (UV-Vis-NIR). This study found that the band gap of ZnO was successfully modified from 3.30 eV to 2.46 eV by combining it with CdS in a composite photocatalyst. The ZnO/CdS photocatalyst exhibited excellent crystallinity and formed a morphology similar to coral as a result of its very intricate three-dimensional geometric structure. The photocatalytic degradation displayed a remarkable level of activity, influenced by operational parameters including the initial concentration, pH of the safranin solution, and the amount of catalyst. The ZnO/CdS photocatalyst destroyed up to 100 % of the safranin dye solution within 120 min of reaction time using 0.5 g of ZnO/CdS photocatalyst and 300 mL of 5 mg/L of safranin solution, at pH 9. ZnO/CdS has potential as a highly efficient photocatalyst for the degradation of organic pollutants, particularly safranin solution, under LED visible light irradiation.