A Review of Various Materials under Different Conditions for Efficient Photocatalytic Dye Degradation

Large amounts of more toxic dye water have been released into the environment recently as a result of the expansion of the textile industry. There are numerous approaches that have been found and applied to lessen the water's toxicity. One of the processes that operate when there is light illumination is photocatalysis. The electrons in the valence band absorb light illumination when exposed to it, excite the conduction band, and create a hole in the valence band. The dye compounds will be lessened by the recombination of these created electron-hole pairs. Materials for effective photocatalysis are being researched. Many factors affect the photocatalytic performance, including narrow bandgap, high surface area, and good recombination rate. TiO2 is a semiconducting material, however, due to its higher bandgap values, it has a lower potential when exposed to light. This article provides a brief overview of several materials that can be affected by a variety of factors, such as doping, surfactant addition, and composites made of carbon-based materials. It also compares how well each material performs in terms of lowering hazardous pollutants and provides an illustration of the mechanism. 

Keywords: Bandgap, Composite, Doping, Methylene blue, Malachite green, Photocatalysts, Reusage, Rhodamine B, Surfactant, TiO2 , Wastewater management.