The basic concepts of photocatalysis are explored in this chapter. Various
parameters which control and influence the photocatalytic process are studied in
relation to the mechanistic approach. Metal oxides like titanium dioxide, zinc oxide,
cerium oxide, tungsten oxide and bismuth oxides play an important role in
photocatalysis for environmental remediation, water splitting and solar cells. The
phenomenon of photocatalysis is dependent on wavelength of incident light. However,
the efficiency of most of the metal oxides is limited in the UV range. It is needed to
modify their band gap energy levels. These modifications can be achieved by doping or
coupling of metals, non-metals, metal oxides and carbon based materials. Metal oxides
morphologies also affect the photocatalytic process due to enhanced surface area and
surface defects providing more accessible sites for the diffusion of organics. Some new
types of materials like perovskite and metal organic framework (MOF) are used as
efficient photocatalysts. The role and mechanism of these materials have been
discussed. All these nanomaterials are used for the environmental remediation, dye
sensitized solar cells, air purifications, hydrogen production and self-cleaning process.
Keywords: Carbon materials, Metal organic frameworks, Metal oxides,
Nanostructures, Quantum dots.
