Metal oxide-based ternary nanocomposites for wastewater treatment

Abstract Industrial effluent (from textile, fertilizer, paper industries, pharmaceuticals, soap, etc.) usually contains a wide variety of pollutants such as dyes, pesticides, surfactants, oil and grease, antibiotics, various metal ions, auxiliary chemicals, etc. The release of poisonous pollutants is extremely destructive to aquatic life. Hence, the wastewater contaminants need to be effectively treated and removed before being discharged into water bodies. Sustainable environmental remediation is currently one of the main global challenges. Heterogeneous photocatalysis plays a significant role in wastewater treatment. Photocatalytic semiconductor materials such as metal oxides (alone as well as binary/ternary nanocomposites) are being used efficiently for the degradation/removal of harmful organic pollutants from wastewater. In this chapter, recent studies related to wastewater treatment using metal oxides and their ternary nanocomposites have been presented. The main focus is on the versatility and combination of various semiconductor materials to get ternary arrangements, which are useful to increase the visible light response of photocatalysts as well as to avoid recombination of light-induced electrons and holes. The ternary metal oxide nanocomposites are considered as advanced photocatalytic materials for degradation of detrimental pollutants. Additionally, it is reported that the rational design of ternary nanocomposites shows the interaction between different metal oxides and helps in water remediation applications.