Mohammed Rehan Katiyan, M D Furqaan Valiyathur, A Ahmed Raza, Z Ansar Ali, Anver Basha Kottur, S Zaheer Ahmed, Mohammed Safiullah Sakvai
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引用次数: 0
Abstract
The persistent challenge of organic dye pollution necessitates the development of innovative and sustainable photocatalytic solutions. This study presents a self-optimizing hydrogel bead photocatalyst, comprising of graphene oxide-copper oxide (GO-CuO) nanocomposite encapsulated within a calcium alginate (CaAlg) matrix leading to the formation of CaAlg/GO-CuO, for enhanced degradation of methylene blue (MB) under UV-Vis light irradiation. Notably, the system enables in-situ reduction of Graphene oxide (GO) to reduced graphene oxide (rGO), significantly enhancing photocatalytic efficiency while allowing for facile catalyst recovery. The composite was characterized using Fourier Transform Infrared (FT-IR) Spectroscopy, X-ray Diffraction (XRD), Raman spectroscopy, Scanning Electron Microscopy-Energy Dispersive X-ray Analysis (SEM-EDAX), and UV-Vis Diffuse Reflectance Spectroscopy (UV-Vis DRS) techniques. Photocatalytic tests demonstrated a remarkable 99 % degradation of MB within 120 min using CaAlg/GO-CuO, compared to 74 % with GO-CuO. Kinetic analysis revealed a 2.5-fold increase in the degradation rate constant, attributed to improved charge separation and enhanced mass transfer facilitated by the alginate matrix. Mechanistic investigation uncovered a dual-phase photocatalytic process: an initial type-II heterojunction-driven mechanism (0-60 min), followed by a Schottky junction-dominated pathway (60-120 min), triggered by in-situ photoreduction of GO to rGO. This transition improved electrical conductivity, suppressed charge recombination, and optimized electron transport pathways.
期刊介绍:
Carbohydrate Polymers stands as a prominent journal in the glycoscience field, dedicated to exploring and harnessing the potential of polysaccharides with applications spanning bioenergy, bioplastics, biomaterials, biorefining, chemistry, drug delivery, food, health, nanotechnology, packaging, paper, pharmaceuticals, medicine, oil recovery, textiles, tissue engineering, wood, and various aspects of glycoscience.
The journal emphasizes the central role of well-characterized carbohydrate polymers, highlighting their significance as the primary focus rather than a peripheral topic. Each paper must prominently feature at least one named carbohydrate polymer, evident in both citation and title, with a commitment to innovative research that advances scientific knowledge.