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.