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چکیده
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In this work, a novel photoactive cellulose-based hydrogel was prepared by simultaneous AgCl formation andentrapment inside Al (III) and Fe (III) cross-linked carboxymethyl cellulose beads. Physio-chemical and opticalproperties of the synthesized composites were well characterized by X-ray diffraction (XRD) analysis, scanningelectron microscopy (SEM), energy dispersive X-ray (EDX) analysis, elemental mapping, Fourier transform in-frared (FTIR) spectroscopy, photoluminescence (PL), and diffuse reflectance spectroscopy (DRS). The photo-catalytic activity of hydrogels was evaluated by the degradation of rhodamine B (RhB), as a model environ-mental pollutant. A comparative study showed that different cross-linkers resulted in different AgCl content,optical properties, and photocatalytic performance of hydrogel beads. Ag/AgCl@Al-CMC and AgCl@Fe-CMCcomposites exhibited remarkable photocatalytic performance (98 % and 87 % removal efficiency within 60 min,respectively) under visible light irradiation, and the effect of operational factors contributing to the photo-catalytic process, including catalyst dosage, dye concentration, and initial pH was investigated. Scavengingexperiments indicated that photo-induced hole and hydroxyl radical made a significant contribution to thedegradation of RhB, and a plausible reaction pathway for the generation of major active species was proposed,according to the calculated band edge potentials of the photocatalysts. Reusability experiments revealed that thedecolorization performance of the photoactive beads decreased afterfive repetitive experiments. This declinewas attributed to the partial photocatalyst leaching from CMC polymeric network into the aqueous environment,evidenced by the results of ICP-OES analysis. The present study opens a new avenue for the development ofhydrogel-based photoactive materials.
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