Abstract
Water is essential for all living things, whether it is human beings, animals
or plants. Around 70% of the total earth's surface is covered by water, however only a
small fraction of it (2.5%) is found as fresh water. On the other hand, due to
anthropogenic activities like industrialization, a huge increase in population, utilization
of toxic chemicals in agricultural activities etc., the available freshwater bodies have
been contaminated by various kinds of pollutants, including toxic chemicals released
mainly from industries like textile, which causes hazardous to both human being and
aquatic life. Therefore removal of these toxic chemicals before entering into fresh
water bodies is of great importance. Heterogeneous semiconductor photocatalysis is the
most effective green method in this regard because it enables to degrade the pollutants
into non hazardous products like CO2
and H2O without releasing any harmful residue.
Therefore, understanding the knowledge of photocatalysis mechanism is very
significant to enable further improvement. Hence, this chapter presents the basic
mechanism of photocatalysis, its drawbacks and the advanced strategies to improve the
catalytic efficiency. Finally some of the important factors that provide strong
influences on the catalytic activity also have been discussed.