Fabrication of carboxymethyl cellulose/graphene oxide/ZnO composite hydrogel for efficient removal of fuchsin dye from aqueous media

Hydrogels are hydrophilic, insoluble, and highly porous 3D networks capable of absorbing large amounts of water. This study aimed to develop a carboxymethyl cellulose/graphene oxide (CMC/GO) hydrogel, cross-linked with citric acid and modified with zinc oxide (ZnO) nanoparticles (CMC/GO/ZnO), synthesized via the sol-gel method. The formulated composite hydrogel samples were characterized by Fourier transmittance infrared spectroscopy (FTIR), scanning electron microscopy (SEM) analysis, X-ray diffraction (XRD), transmission electron microscopy (TEM), and thermo-gravimetric analysis (TGA). The hydrogels were tested for the adsorption of basic fuchsin (BF) dye from the aqueous medium under various conditions, such as adsorbent dosage, contact time, pH, and temperature, using batch adsorption. The adsorption data best fit the Langmuir and Temkin models, with maximum adsorption capacity (q