Polymer-Based Photocatalysis for Remediation of Wastewater Contaminated with Organic Dyes

Abstract

Photocatalysis is an eco-friendly strategy to clean polluted waters under ambient conditions using sunlight or artificial light sources. Photocatalysis can degrade different classes of organic dyes into simple bio-assimilable species or less toxic components, and even mineralize them into harmless CO2 and H2O without leaving undesired byproducts. The utilization of polymer-based photocatalysts in the remediation of wastewater is initially motivated by several economic advantages such as facile separation and reuse, flexible designs, effectiveness, low cost and availability. Polymeric photocatalysts include photo-inactive polymers loaded with conventional photoactive species such as transition metal oxides, plasmonic metals and metal complexes. Some organic polymers are photoactive, possess outstanding semiconductive features and are notably capable of photocatalytically degrading organic dyes pollutants in water. The photocatalytic performance of the conventional photoactive species can be drastically improved when combined with the photoactive polymers. This chapter summarizes the latest representative advances of polymers in the photocatalytic treatment of wastewater contaminated with organic dyes. It begins with an introduction that includes a short general background on the importance of photocatalysis in the remediation of organic dyes, particularly with respect to polymeric photocatalysis. Then, a comprehensive overview of the conventional and up-to-date polymer-based photocatalysts is introduced, exploring their different types and the proposed mechanistic pathways. The commonly used techniques for the characterization of polymer-based photocatalysts are then concisely explored. The gained advantages, as well as the activity evaluation approaches, are also addressed. Finally, in conclusion, the future perspectives, recommendations and existing challenges are outlined.KeywordsPolymer compositesMetal nanoparticlesPhotocatalytic efficiencyUV/visible lightSunlightConjugated polymerConducting polymerCoordination polymerPorous organic polymerOrganic dyesTextile wastewaterWater treatmentPhotocatalysis