Engineered Heterostructure Photocatalyst: Chitosan-Coated Chromium Ferrite/Graphite Oxide Synthesized Hydrothermally for Environmental Remediation

This study reports the hydrothermal synthesis and characterization of a chitosan-coated chromium ferrite/graphite oxide (CrFe2O4/GO/CS) nanocomposite with enhanced photocatalytic performance. The unique combination of the semiconductor properties of chromium ferrite, the light-harvesting capabilities of graphite oxide, and the stabilizing and adsorptive properties of chitosan resulted in a synergistic enhancement of the photocatalytic activity. The nanocomposite was characterized using FT-IR, Raman, XRD, zeta potential, DRS, BET, SEM, and EDS techniques. BET analysis revealed a specific surface area of 418.56 m(2)/g and a pore diameter of 2 nm for the CrFe2O4/GO/CS nanocomposite. The band gap of the nanocomposite was determined to be 3.5 eV, compared to 2.9 eV for CrFe2O4 and 2.95 eV for CrFe2O4/GO. The photocatalytic performance was evaluated through the degradation of Reactive Red 198 (R198) and Brilliant Blue FCF 133 (B133) dyes under UV and sunlight irradiation. The CrFe2O4/GO/CS nanocomposite demonstrated superior dye removal efficiency compared to CrFe2O4 and CrFe2O4/GO, achieving up to 98.2% removal for R198 at pH 8 and 98.5% for B133. The nanocomposite also showed excellent reusability, maintaining 81% removal efficiency for R198 and 77.6% for B133 after three cycles. Kinetic studies revealed that the dye removal process followed a pseudo-second-order model with R-2 values of 0.99 for both dyes. The nanocomposite demonstrated effective performance in real textile wastewater treatment, achieving 91.5% dye removal efficiency. The enhanced photocatalytic performance, coupled with the nanocomposite's reusability, highlights its potential for practical applications in water purification and environmental remediation.