Eco-friendly synthesis of reduced graphene oxide as sustainable photocatalyst for removal of hazardous organic dyes

Abstract

Synthetic dyes are widely used as coloring agents in the textile, food, paper, leather, and printing industries. Sustainable removal of these dye molecules is a challenging task due to their toxic nature to the environment as well as for living organisms. In the present study, a simple hydrothermal method is carried out to synthesize reduced graphene oxide (rGO) using the leaves extract of Murraya koenigii. Further, different characterization techniques such as X-ray diffraction, Raman spectroscopy, UV–vis spectroscopy, and Fourier transform infrared spectroscopy (FT-IR) are used to confirm the physicochemical properties of synthesized rGO. Raman analysis confirms the reduction of graphene oxide by the increase in ID/IG ratio significantly. Field emission scanning electron microscopy (FE-SEM) and Transmission electron microscopy (TEM) analysis show well-exploited rGO morphology. Further, newly synthesized rGO is used as a photocatalyst for the removal of methylene blue (MB) and methyl orange (MO) dyes. UV–vis spectrophotometer is used for monitoring the degradation efficiency. Catalyst MKrGO shows 80% of MO and 77% of MB degradation within 120 min of sunlight exposure. The sustainability of this catalyst is checked by recyclability in five subsequent degradation cycles and noticed a stable and significant degradation activity.

Keywords

• Reduced graphene oxide
• Green synthesis
• Murraya koenigii
• Photocatalytic activity
• Dye removal