Synthesis of r-GO/PANI/ZnO based material and its application in the treatment of wastewater containing Cd<sup>2+</sup> and Cr<sup>6+</sup> ions
Naveen Chandra Joshi
Abstract
This work provides an environmentally friendly synthesis of zinc oxide nanoparticles (ZnO NPs) using Syzygium cumini (Jamun) leaves extract and their incorporation with reduced graphene oxide (r-GO) and polyaniline (PANI) to form r-GO/PANI/ZnO. XRD, SEM, EDX, and FTIR techniques were used to characterize the r-GO/PANI/ZnO nanocomposite, which was then used to remove hazardous Cd2+ and Cr6+ ions from aqueous media. FTIR spectroscopy has confirmed the presence of N-H, C = O, C = N, C = C, C-C, C-Zn, Zn-O etc. bonds on the surface of r-GO/PANI/ZnO; the XRD pattern of r-GO/PANI/ZnO indicates its amorphous nature. Different batch parameters were used to perform the adsorption-based removal. The optimal conditions for maximum water decontamination have been identified. Different isotherm and kinetic models were used to test the experimental findings. Maximum adsorption capacities of r-GO/PANI/ZnO were found to be 12.033 and 22.522 mg/g for Cd2+ and Cr6+ ions, whereas rate constants (k2) observed as 1.547 and 84.033 g/mg/min, respectively.