Solar-Driven Photocatalytic Degradation of Clothianidin Using Green NiO-GO Composite

The extensive use of clothianidin pesticide poses significant risks to non-target organisms and water resources. In this study, NiO-GO is reported as an effective photocatalyst for the degradation of clothianidin in aqueous medium. Nickel oxide (NiO) nanoparticles were synthesized by a green method using Pisum sativum (pea) peel extract, which serves as a natural reducing and stabilizing agent, and subsequently integrated with graphene oxide (GO) through ultrasonication to form a NiO-GO composite in a 1:1 ratio. The materials were characterized by various techniques. Photocatalytic degradation of clothianidin under natural sunlight was systematically investigated, assessing the effects of pH, catalyst dosage, initial pollutant concentration, and agitation speed. The NiO-GO composite exhibited superior photocatalytic performance (96% degradation at pH 3 within 60 min) compared to pristine NiO and GO, with a rate constant 4.4 and 3.3 times higher, respectively. The as-prepared NiO-GO photocatalyst exhibited nearly consistent degradation efficiency over two successive cycles, demonstrating its excellent structural stability and reusability. The enhanced performance is attributed to improved charge separation afforded by GO support. This low-cost, green, and efficient NiO-GO photocatalyst demonstrates promising potential for sustainable pesticide remediation in aqueous environments.