Engineered TiO2 photocatalyst – Mechanism, kinetics, and application in dye removal: A review

Department of Civil Engineering, Indian Institute of Technology Hyderabad, Hyderabad-502 285, Telangana, India E-mail: ambika@ce.iith.ac.in Manuscript received online 02 December 2020, accepted 23 December 2020 Rapid industrialization and escalating urbanization generate a huge quantity of wastewater with a continuous surge in the wide variety of organic pollutants. Heterogeneous photocatalysis, an advanced oxidation process is highly efficient, robust, sustainable, economical, and effective treatment technology for the detoxification of dyes from the aqueous phase with strict adherence to the green chemistry principle. Modification and development of an advanced photocatalytic system for macroscale industrial application require deeper cognizance of the mechanism and kinetics of charge transfers involved in photocatalytic reaction for the treatment of industrial dye effluents. Therefore, this review aims to detail the kinetic model and compiles the photodegradation of various dyes using TiO2 as the photocatalyst. Correspondingly, the present study recapitulates the application of different dopants and co-dopants along with their synthesis method in enhancing the TiO2 photocatalytic efficiency for dye removal. This paper provides complete information on photocatalysis which can be used for the effective degradation of textile dyes from an aqueous system