Preparation and application of α-Fe₂O₃/TiO₂/activated charcoal plate nanocomposite as an electrode for electrosorption-assisted visible light photoelectrocatalytic process

A novel α-Fe₂O₃/TiO₂/activated charcoal plate (α-Fe₂O₃/TiO₂/ACP) nanocomposite was prepared by electrophoretic deposition method and characterized by X-ray diffraction, transmission electron microscope, scanning electron microscope, and energy dispersive X-ray. The prepared nanocomposite was used as an electrode for decolorization of reactive yellow 39 solution using a new electrosorption-assisted electrophotocatalytic process under visible light irradiation. Response surface methodology was used to model and optimize the decolorization process. The dye concentration of 10 mg L^-1, Na₂SO₄ concentration of 7.9 g L^-1, voltage of 700 mV, and time of 150 min were achieved as optimum conditions. Results showed that the decolorization efficiency in electrosorption-assisted visible light photoelectrocatalytic process using α-Fe₂O₃/TiO₂/ACP nanocomposite was higher (94%) compared with those of TiO₂/ACP (45%) and α-Fe₂O₃/ACP (60.26%) at optimum conditions. Moreover, the decolorization efficiency of 28.55% in adsorption, 43% in electrosorption, and 38.1% in photocatalytic processes were achieved using α-Fe₂O₃/TiO₂/ACP nanocomposite at optimum conditions. The obtained results indicated that electrosorption-assisted photoelectrocatalytic process using α-Fe₂O₃/TiO₂/ACP nanocomposite was more effective than other processes in the decolorization of the contaminated water.