The synergistic triad of graphene quantum dots, polymer, and ferrites for the photodegradation of dyes in aqueous solution

Abstract

This work aimed to investigate photocatalytic properties of GQDs@PEG@Mg–ZnFe2O4 nanocomposite, composed of graphene quantum dots (GQDs), polyethylene glycol (PEG), and Mg–ZnFe2O4, for the degradation of methylene blue (MB) and crystal violet (CV). This nanocomposite was synthesized using facile ultrasonics-assisted methodology. XRD analysis confirmed the formation of the spinel structure of the Mg–ZnFe2O4 in the nanocomposite, whereas the presence of GQDs and PEG was confirmed by Fourier transform infrared spectroscopy. Scanning electron microscopy (SEM) revealed a reduction in agglomeration and particle size in the ternary nanocomposite. The GQDs@PEG@Mg–ZnFe2O4 nanocomposite demonstrates a remarkable degradation efficiency of 98 % for CV and MB dyes in the presence of sunlight in 120 min, indicating its potential as an efficient photocatalyst. Vibrating sample magnetometer (VSM) analysis confirmed the superparamagnetic behavior of the GQDs@PEG@Mg–ZnFe2O4 nanocomposite which enables magnetic recovery of the photocatalyst after the degradation process. Overall, this study emphasizes the utilization of an environmentally friendly approach to effectively eliminate organic pollutants from wastewater, addressing a crucial environmental concern.

Keywords

• Mg-ZnFe2O4
• Graphene quantum dots (GQDs)
• Ternary nanocomposite
• Methylene blue (MB)
• Crystal violet (CV)
• Photocatalytic degradation