Photocatalytic degradation of organic pollutants using TiO₂-based photocatalysts: A review

Organic compounds, generated from different industries, produce a range of the problematic pollutants in wastewater. TiO₂ based photocatalysts are novel materials that exhibit excellent absorption behavior toward organic compounds in wastewater due to their outstanding properties including nontoxicity, high photocatalytic degradation ability, and excellent thermal and chemical stabilities. However, several challenges exist regarding TiO₂ applications for organic effluents such as particle aggregation, mass transfer limitation, poor affinity, high band energy, scattering conditions, and difficulty of recovery. Therefore, more design and optimization testing need to be conducted on the treatment conditions in order to reach higher removal efficiencies with lower costs. A variety of parameters of TiO₂ based photocatalysts need to be studied: substrate, light intensity, dopant, particle size, structure. These parameters, which affect TiO₂ photocatalytic activity on organic pollutants, are discussed in the current review. Thus, making the photocatalyst more anticipated and conducive to further research and development.