<![CDATA[Background: Wastewater containing dyes occurs due to the discharge of wastewater into rivers without undergoing proper treatment procedures as it should. This waste generally comes from the textile industry. Wastewater containing dyes increases the concentration of organic pollutants in wastewater, which can cause water pollution. Textile dyes are generally made from compounds containing aromatic rings, such as methyl orange and methylene blue. Methyl orange and methylene blue are organic pollutants that cannot be biologically degraded because they contain aromatic rings that are difficult to break down, thus posing a risk of environmental pollution and disrupting aquatic ecosystems. Several conventional wastewater treatment methods for dye degradation, such as coagulation, flotation, sedimentation, and filtration, have been applied, but these methods still have limitations. Methods: This review examines recent progress in the development of TiO₂ nanotube-based photoelectrodes modified with Co₃O₄ and noble metals (Ag, Au) for the degradation of methyl orange and methylene blue from wastewater. The use of electrochemical methods has advantages over conventional methods, namely more efficient, environmentally friendly, and flexible for the degradation of dyes in wastewater. The synthesis techniques used are anodization, impregnation-deposition-decomposition, and photodeposition methods. Findings: The development of TiO₂/Co₃O₄/Ag and TiO₂/Co₃O₄/Au nanotube-based photoelectrodes shows better performance in the degradation of organic dyes compared to unmodified TiO₂ photoelectrodes, as they can improve photocatalytic efficiency by expanding visible light absorption and increasing surface reactivity. Conclusion: The use of TiO₂/Co₃O₄/Ag and TiO₂/Co₃O₄/Au materials has great potential as an environmentally friendly and efficient solution in addressing pollution from persistent textile dye wastewater. The implementation of this technology in industrial wastewater treatment systems promotes advances in the fields of photocatalysis and renewable energy. Novelty/Originality of this article: This review is the first to evaluate TiO₂ nanotube/Co₃O₄ photoelectrodes modified with Ag and Au for the degradation of methyl orange and methylene blue.]]>
