Arginine-polyaniline@g-C 3 N 4 for outstanding retention of Orange G dye from water

An eco-friendly material was synthesized through interfacial polymerization of aniline on particles of g-C 3 N 4 with arginine, resulting in Arg-PANI@g-C 3 N 4 composite. The as-synthesized composite was characterized by the Brunauer, Emmett, and Teller (BET) surface area, X-ray energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The adsorption capability of as-synthesized composite towards Orange G (OG) dye has been evaluated under several experimental conditions, such as the adsorbent dosage, initial dye concentration, contact time under agitation, pH of dye solution and temperature. Thermodynamics parameters such as free energy (ΔG°), entropy (ΔS°), and enthalpy (ΔH°) were also calculated and suggested that the adsorption process is spontaneous and endothermic in nature. The kinetics data revealed that the adsorption of OG dye onto Arg-PANI@g-C 3 N 4 follows the pseudo-second order kinetics model. The maximum adsorption capacity was found to be 80.54 mg·g −1 . Furthermore, the Arg-PANI@g-C 3 N 4 surface exhibited a Langmuir-like adsorption isotherm in contrast to a Freundlich isotherm due to homogeneous active site distribution. Regeneration investigation showed the excellent reusability of Arg-PANI@g-C 3 N 4 composite during the cleaning up of solution containing OG dye molecules.