Green Synthesis of Nano-Semiconductor Photocatalysts and their Effectivity for Photo-Oxidation of Organic Pollutants in Wastewater: A Review Study

Abstract

In recent years, green synthesis of nanoparticles (NPs) has been regarded as preferable and acceptable than chemical approaches, particularly when it applies to pollution control and wastewater treatment. The green synthesis approaches were effectively employed to prepare a huge number of semiconductors photocatalysts, such as TiO2 , WO3 , SnO2 , CeO2 , ZnO, Bi2 O3 , Ag, Na2 SeO3 , ZnCr2 O4 , Nb2 O5 , and so on. Photocatalytic degradation is an advanced water treatment technology that has great potential for the photo-oxidation of various organic pollutants and various types of nano-semiconductors photocatalysts. Plant waste has the potential to be more useful in the green synthesis of metal nanoparticles (NPs) due to their availability, high biodiversity, eco-friendliness, and low cost. This review focuses on the employing of plant extracts in the synthesis of nano-photocatalysts as a cost-effective approach. Our study involves reviewing a huge number of impactful studies that deal with the photooxidation of organic pollutants under light radiation. It was concluded that the utilization of waste plants in the green synthesis of nano-photocatalysts is a low-cost technology, environmentally friendly, and can produce nanoparticles with outstanding efficiency for water pollution remediation. This study encourages the development of new technologies based on reusing plant waste in the synthesis of economic photocatalysts for environmental applications.