Nanomaterial for photocatalysis and their application in environmental clean-up

In recent years, nano-based photocatalyst has shown a great potential as a low-cost, green chemical based and sustainable waste water treatment technology. Development of materials for photo oxidation and photocatalysis has followed an evolutionary pathway from usual bulk metals and semiconductors to colloidal materialsand, recently, to nanosized materials. Nanosized materials, whose electronic properties are size-tunable, enable the application of a larger range of semiconductors as a potential material for photocatalytic processes in the fieldof environmental remediation. The continuous worsening environmental pollution and energy shortages have raised awareness of a potential global crisis. For the sustainable development of the ecologicalsociety, the development of pollution-free and green chemistry based technologies for environmental remediation is an urgent need. Among the wide variety of green earth and renewable energy projects underway, nano-photocatalysis has emerged as one of the most promising new technology because it represents an easy way to utilize the energy of either natural sunlight or artificial internal illumination, and is available abundantly everywhere. Nano-photocatalysis is a rapidly expanding technology for the removal as well as the mineralization of toxicants from the waste in order to environmental clean-up and sustainable development. The ability of this advanced oxidation technology has been extensively demonstrated to remove persistent organic compounds, toxicants, pesticides and dye effluents from the waste water. This paper reviews the recent R&D progresses of semiconductor nano-photocatalyst, mechanism, affects, present and future prospectus of photo oxidation processes for waste water treatment.