Title : Photocatalysis: A promising green chemical pathway
Abstract:
The world is facing two major problems these days. These are: (i) Rapidly developing water and air pollution and (ii) Upcoming shortage of natural resources of energy. Advanced Oxidation Processes are green chemical pathways, where photocatalysis has emerged as one of the promising processes. It can provide a solution to both these burning issues and that too simultaneously. Hydrogen has been long advocated as a fuel of future as all conventional fuels are likely to be exhausted within coming two decades or so. It can be generated from photosplitting of water photocatalytically. Global warming is another existing challenge of concern, and here, the carbon dioxide has been considered as the main culprit. Carbon dioxide can also be reduced photocatalytically to some useful value added fuels. But many photocatalysts have two major limitations. In most of the cases, their activity is limited because of little or no absorption in visible range and rapid recombination of electron- hole pairs. Both these limitations can be overcome by increasing the photocatalytic activity through modifying semiconductors by use of cocatalysts, composite formation, metal or non-metal doping, sensitization, S-Scheme, Z-scheme, etc. This will be discussed with some other interesting applications of photocatalysis.
