Fundamentals of electrocatalysis and photocatalysis for the remediation of wastewater containing methylene blue

Abstract

The textile industry is a significant source of water pollution. Methylene blue (MB) dye from textile effluents is the most visible source and studied treatment method to prevent adverse effects on human health and aquatic systems. Here, we present a comprehensive review on applying photocatalyst-based AOPs and electrocatalysis methods as efficient and environmentally friendly techniques to degrade MB. The types of electrocatalytic techniques, their advantages, and the main factors affecting their performance are comprehensively reviewed. In contrast, an assessment of the important parameters of photocatalytic techniques is summarised and extensively discussed. In addition, the mechanisms and by-products generated are analysed to improve the understanding of advanced textile wastewater treatment. Synergistic effects in hybrid AOPs (integration of photocatalytic and electrocatalytic techniques) are also discussed as an improved technique. Furthermore, our review article discusses the future direction of photocatalyst and electrocatalysis-based AOP methods, emphasising the need for sustainable, cost-effective, and environmentally friendly solutions.

Keywords: Advanced oxidation processes; Electrocatalysis; Methylene blue; Photocatalyst.