Development and characterization of fluorescent cellulose succinate hydrogels for efficient chromium adsorption

This study focuses on developing and characterizing of fluorescent cellulose-based hydrogelsfor efficient chromium (Cr(VI)) adsorption. For this purpose, microcrystalline cellulose (MCC) was first surface-modified to achieve solubility using succinic anhydride. Cellulose succinate (CS) subsequently was grafted with a mixture of acrylic acid (AA) and acrylamide (AM), while N,N′-methylene-bis(acrylamide) (MBA) was added as crosslinker to obtain the final grafted and crosslinked hydrogels. To impart fluorescence and sensing capabilities, nitrogen-doped carbon quantum dots (N-CQDs) were synthesized via a microwave-assisted method using sugarcane bagasse, NaOH, and urea as precursors, and incorporated into the hydrogel. The resulting hydrogels demonstrated effective Cr(VI) adsorption, with optimal performance observed at 10% N–CQD loading. FTIR, SEM, rheological analysis, and TGA were employed for hydrogel characterization, while adsorption kinetics provided insights into the interaction mechanisms with Cr(VI).