Recent advances in removal of pharmaceutical pollutants in wastewater using metal oxides and carbonaceous materials as photocatalysts: a review

Abstract

The pharmaceuticals industry has played an important role in developing medicines for improving health and quality of life in treating humans and animals around the world. But it is also considered to be one of the sources of pollutants entering deliberately or accidentally into global water bodies causing toxicity that eventually threatens human health, aquatic organisms and environments even at low concentrations. These contaminants are non-biodegradable and cannot be completely removed from various water matrices following conventional treatment methods. In this regard, photodegradation techniques involving modified/unmodified semiconducting materials have attracted a lot of attention as a promising solution in achieving complete antibiotic degradation with the generation of non-toxic by-products. In view of this, the present review article summarizes current research progress in the removal of several emerging contaminants, such as acetaminophen, amoxicillin, sulfamethoxazole, norfloxacin, ibuprofen, ciprofloxacin, tetracycline, diclofenac and atenolol in water. Considerable emphasis has been placed on metal oxides and carbon-based photocatalysts following their modification through doping with metals and non-metals, metal loading, the formation of composites, immobilization and heterostructure/heterojunction approaches. Finally, the review ends with future prospects for nanomaterial-based heterogeneous photocatalysts in the removal of pharmaceutical contaminants from water.