Preparation and Applications of Non-Metal Doped Semiconductors as Photocatalysts

Water is one of the most essential commodity for mankind, but we know that only 1% of available water on earth may be used for human consumption. However, due to increasing anthropogenic activities the water is getting polluted. Scientists all over the world are looking for ecofriendly methods to treat polluted water for its reuse. One technique that has been gaining popularity in recent years and it is quite promising also for the treatment of resilient pollutants is the photocatalysis. Numerous studies have been reported in the last decade on the photocatalytic degradation of organic pollutants using semiconductor materials as photocatalysts, but the limited optical absorption due to the relatively wide band gap energies and recombination of photogenerated electron-hole pair results in low activity of photocatalysts. Therefore, improvement of charge separation as well as enhancement of visible light absorption is highly important for the efficient photocatalytic reactions. In this context, doping of semiconductor by non-metals seems a promising strategy to enhance the activity of a photocatalyst. In this chapter; preparation, characterization, mechanism and various applications of non-metal doped semiconductors has been reported and the applications of semiconductors have been focused on waste water treatment. Some other applications include generation of hydrogen by photocatalytic splitting of water, antimicrobial activity etc.