Facile Hydrothermally Synthesized 2D-Based rGO/NiO Nanohybrid for Environmental Remediation of Malachite Green Pollutant

This study produced rGO/NiO nanohybrid through a simple hydrothermal strategy for photocatalytic degradation of noxious malachite green (MG) pollutants. Nanocomposites’ chemical structure was verified by X-ray diffraction (XRD), ultraviolet visible spectroscopy (UV–Vis. Spectroscopy), X-ray photoelectron spectroscopy (XPS) analysis and Raman spectra. Bandgap narrowing of nickel oxide was observed by UV–Visible spectroscopy after its integration with rGO. In terms of photocatalytic efficiency, rGO/NiO nanocomposites show remarkable efficiency (96.15%) in degrading malachite green dye than NiO (81.73%) under 120 min. rGO/NiO nanocomposites exhibit a 0.006 min −1 rate constant, which is 2% greater than bare nickel oxide. The scavenging analysis demonstrated that hydroxyl radicals and superoxide ion play a vital role in photodegradation. The photocatalyst’s repeatability was determined through a cyclic test. The remarkable photocatalytic efficiency was obtained due to the synergetic behavior of rGO and NiO. rGO provided a greater surface area exhibiting greater number of active zones responsible for the adsorption of electrolyte ions. This rGO/NiO nanohybrid has been employed as a photocatalyst in efficiently removing noxious pollutants from wastewater.