Industrial & Engineering Chemistry Research, Vol.52, No.46, 16162-16168, 2013
Bifunctional Titania Float for Metal Ion Reduction and Organics Degradation, via Sunlight
The present study demonstrates the use of a bifunctional titania float in sunlight to cause the simultaneous oxidation of formic acid and reduction of Cr(VI) to Cr(III). Nanosized anatase TiO2 was synthesized by wet chemical methods and characterized by various microscopy and spectroscopy techniques. A float has been fabricated with the above nanopowder for water purification via sunlight-mediated photocatalysis. The impractical reduction of chromium in sunlight was made feasible by the use of photoactive nanotitania, unlike the UV light, which requires only the acid for complete reduction of chromium. The organic's (formic acid) degradation and Cr(VI) reduction were observed to support each other till the completion of both oxidation and reduction, respectively. Formic acid with the catalyst (in the form of a float) in sunlight causes indirect scavenging of holes to enhance the catalytic efficiency and bring up the reduction rate on par with UV light, making the water purification an environmentally friendly and recyclable process.