Effective removal of methylene blue from aqueous solution using CuCo2O4 -graphene quantum dots nanocomposite as a heterogeneous Fenton-like catalyst

Textile wastewater is one of the major industrial pollution sources in the aquatic environment. The presence of textile materials, especially synthetic dyes in aquatic system poses serious threat to public health since most of them are toxic, mutagenic or potentially carcinogenic to humans, animals and aquatic life in general [1]. Due to increasingly rigorous restrictions on the organic pollutants of industrial effluents, wastewater should be purified from such materials before being discharged to the environment. Several methods have been used for removing dyes from wastewater, including flocculation, membrane filtration, precipitation, biological processes and chemical oxidation [2]. Among the methods that are applicable in the treatment of contaminated aqueous effluents, the advanced oxidation processes (AOPs) have been considered an attractive approach to eliminate toxic or hazardous compounds from aqueous solutions. AOPs are processes that hydroxyl radicals as a strong oxidant agent for degradation of a wide range of contaminants are produced [3]. In this study, a novel nanocomposite based on CuCo2O4 and Nitrogen- doped graphene quantum dots (N-GQDs) was prepared and used as a catalyst for heterogeneous Fenton-like catalyst for degradation of methylene blue. The results showed that catalytic performance were significantly enhanced with incorporation of N-GQDs into CuCo2O4.The nanocomposite was characterized using scanning electron microscopy (SEM), Fourier transform infrared spectrometer (FTIR) and X-ray diffraction (XRD). The important factors affecting the degradation efficiency, including solution pH, catalyst dosage and H2O2 dosage were investigated.