Proceedings of Symposium on Energy Engineering in the 21st Century (SEE2000) Volume I-IV

ISBN Print: 1-56700-132-7

APPLICATION OF PHOTOENERGY ON OXIDATION OF TOXIC NITRITE ION AND HYDROGEN GENERATION USING THE RUTILE FORM OF Ti02/Ti PHOTOELECTRODE

DOI: 10.1615/SEE2000.1600
pages 1257-1264

Abstract

Immobilized Ti02 powder on a conductive supports exhibits interesting electrochemical and photoelectrochemical properties. Ti02 supported on Ti plate, Ti02/Ti, was used as working electrode, and Pt, Ti and graphite were used as counter electrode. The morphology of Ti02 on the Ti plate is rutile form. Experimental results indicate that the rutile form of Ti02/Ti film electrode has excellent photoactivity by applying a bias potential and photoenergy simultaneously. The toxic nitrite ion was destroyed on the TiO2/Ti electrode. Furthermore, the hydrogen generation on the counter electrode also occurred simultaneously during this photoelectrochemical reaction. The rates of both the nitrite ion oxidation and the hydrogen generation are mainly promoted by the applied potential and power of photoenergy. The photocurrent efficiency can be calculated from the measurement of photocurrent and the rate of nitrite ion removal. The photocurrent efficiency of nitrite ion oxidation was 33~40% at a pH of about 7. The photoefficiency of nitrite ion oxidation and hydrogen generation are about 16 and 40 %, respectively. It may be a suitable method for water purification and hydrogen energy generation simultaneously using solar energy.