Eco-Friendly Synthesis and Characterization of Double-Crossed Link 3D Graphene Oxide Functionalized With Chitosan for Adsorption of Sulfamethazine From Aqueous Solution: Experimental and DFT Calculations

Graphene oxide–chitosan composites are attracting considerable interest as an eco-friendly adsorbent material for most aquatic environmental pollutants. Today, the focus is on emerging applications of 2D and 3D graphene functionalized with chitosan to enhance its mechanical properties adsorption efficiency. Herein, super (3D GF-CS) synthesized remove sulfamethazine, (SMZ) a model antibiotic pharmaceutical. The materials were characterized by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), photon (XPS), Brunauer–Emmett–Teller (BET), Raman spectroscopy. After that, experiments conducted SMZ find out optimized parameters, such pH, temperature, contact time, initial concentration, dosage. results show optimal parameters pH 7, temperature 25°C, concentration Ci 50 ppm. Also, kinetics, isotherms models, thermodynamics studied. experimental revealed be best suited both pseudo-second-order kinetic Freundlich isotherm compared other models. demonstrated that exothermic, exhibiting higher efficiency at lower temperature. In addition, Gibb’s free energy suggested spontaneous well entropy indication loss disorder. Furthermore, regeneration GF-CS was utilized in ten consecutive cycles, capacity did not decline significantly. Additionally, this research studied energies how sulfamethazine adsorbs onto determined applying density-functional–based tight binding (DFTB) Monte Carlo simulations different positions. chemical reactivity (local global) drug investigated using density functional theory (DFT), namely, B3LYP PBEPBE functionals 6–31+G (d, p) basis set gas phase aqueous solution.