Effect of Temperature and Retention Time on the Quality of Biochar of Some Agricultural Waste

Abstract

Cadmium sulfide (CdS) thin films have attracted significant attention for environmental remediation applications due to their suitable band gap, high photosensitivity, and excellent photocatalytic properties. In this study, non-aqueous CdS thin films were hydrothermally synthesized using cadmium nitrate tetrahydrate and thiourea as precursor materials in methanol medium. The films were prepared at varying precursor concentrations of 0.10 M, 0.20 M, and 0.30 M. To enhance the photocatalytic performance of CdS, 0/005g of bismuth ferrite (BiFeO₃) and 0.005g tin oxide (SnO₂) were incorporated as dopants in separate preparation. The synthesis was carried out in a Teflon-lined autoclave at 180 °C for 8 h, followed by washing, drying, and pulverization of the obtained products. The structural, morphological, optical, and photocatalytic properties of the synthesized samples were investigated using appropriate characterization techniques. The influence of precursor concentration and dopant incorporation on crystallite size, surface morphology, and optical band gap was evaluated. Photocatalytic activity was assessed through the degradation of methylene blue dye under natural sunlight irradiation. The results revealed that both BiFeO₃ and SnO₂ doping significantly improved the photocatalytic efficiency of non aqueoud CdS to 70.0 & 72.8% respectively by enhancing charge separation and reducing electron–hole recombination. The findings demonstrate that hydrothermally synthesized non-aqueous CdS thin films doped with BiFeO₃ and SnO₂ are promising photocatalysts for the degradation of organic pollutants in wastewater under sunlight irradiation, offering a cost-effective and environmentally friendly approach for water purification applications.