Photocatalytic disinfection of micro-organisms: Mechanisms and applications

Abstract

Microbial contamination has globally represented an extreme health risk to human beings. Bacteria, fungi, algae and viruses being minuscule possess excessive ecological toxicity and a wide range of diseases to an aquatic and terrestrial existence Recently, photocatalytic disinfection has acquired ever-growing worldwide attention due to its energy conversion and disinfection potential. Diverse factors such as the type of photocatalytic material employed for the disinfection process and micro-organisms significantly influence the disinfection technique. There are different novel photocatalysts including TiO2, graphitic carbon nitride (g-C3N4), nanocomposites and membranes that have been developed for microbial disinfection in land and water surfaces. Photocatalytic disinfection is majorly dependent on different operational parameters such as photocatalysts dosage, pH, light source, and temperature. Photocatalysts possess antimicrobial properties which might also contribute to the expulsion of micro-organisms from surfaces. Cell membrane degradation mechanism which governs the performance of photocatalytic disinfection is reviewed in detail. The review describes the fundamental mechanism of photocatalytic disinfection. The development of novel photocatalysts for the disinfection of bacteria, fungi, viruses and algae has been reviewed in detail. In addition, different parameters that affect the performance of photocatalytic disinfection are reviewed. Applications of photocatalytic disinfection of microorganisms and future perspectives are discussed.