Environmentally friendly reduction of graphene oxide using the plant extract of novel Chromolaena odorata and evaluation of adsorption capacity on methylene blue dye

Abstract

Chromolaena odorata is an extremely allelopathic and commonly available herb that conquers neighbouring vegetation, and research is being conducted to utilize it for a wide diversity of applications. In the current study, methylene blue dye (MB) is decomposed by exploring the suitability of novel C. odorata for achieving reduced graphene oxide (RGO) through a simplistic green synthesis method. C. odorata assisted RGO is characterized using X-ray diffraction study, scanning electron microscopy, Raman spectroscopy, UV–visible spectrophotometry, photoluminescence spectroscopy and Fourier transform infrared spectroscopy. These characterizations indicate that the synthesized RGO has a UV–visible absorbance peak at 270 nm, an X-ray diffraction reflection peak at 2θ = 2.12°, and a Raman spectrum having an I D /I G ratio of nearly 0.98. Moreover, the RGO sample exhibits excellent MB dye scavenging efficiency having an adsorption amount of 300 mg/g. The adsorption kinetics is also investigated which established that adsorption fits very well with pseudo-second-order kinetics. Furthermore, the thermodynamics behaviour of the RGO sample has been carried out and demonstrated that adsorption is endothermic and spontaneous. The present study offers appropriate visions for the eco-friendly reduction of graphene oxide by C. odorata and utilizing it for the remediation of organic dye.