Photochemical production of hydrogen from alkaline solution containing polysulfide dyes
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Efficient hydrogen production was achieved by irradiating solutions containing polysulfide dyes as a photoabsorber. In the presence of polysulfide only, considerable amount of hydrogen was initially evolved and followed by the rapid decrease of the evolution rate. On the contrary, in the co-presence of NiOxx< l/TiO2 and polysulfide, steady evolution of hydrogen was observed even after long period of illumination. The photocatalytic evolution of hydrogen was divided into two stages: i) in the first stage within 1 hour irradiation, the hydrogen evolution rate was abruptly increased due to the conversion of polysulfide to partially oxidized sulfur, S2O x 2- ii) in the secondary stage after 1 hour irradiation, steady evolution of hydrogen was observed due to the conversion of partially oxidized sulfur to fully oxidized sulfur. The oxidation/reduction of sulfur occurred more favorably over SiC catalyst where more steady evolution of hydrogen was achieved.
Key wordsHole Scavenger Polysulfide NiO/TiO2 SiC Hydrogen Evolution
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- Kawai, T. and Sakata, T., “Photocatalytic Hydrogen Production from Liquid Methanol and Water”,J. Chem. Soc., Chem. Comm., 694 (1980).Google Scholar
- Lee, S. G. and Lee, H.-I., “A New Active Sulfur-Sensitive Bismuth Oxide on Titania for Photocatalyst”,Korean J. Chem. Eng.,15, 463 (1998).Google Scholar
- Pellizetti, E., Borgarello, N., Serpone, N. and Grätzel, M., “Catalysis on the Energy Scene”, Studies in Surface Science and Catalysis, Kaliaguine, S. and Mahay, A., eds., Elsevier, Amsterdam (1984).Google Scholar
- Pichat, P., Herrmann, J.-M., Disdier, J., Courbon, H. and Mozzanega, M.-N., “Photocatalytic Hydrogen Production from Aliphatic Alcohols over a Bifunctional Platinum on Titanium Dioxide Catalyst”,Nonv. J. Chim.,5, 627 (1981).Google Scholar
- Rabek, J. F., “Experimental Methods in Photochemistry and Photophysicsf John Wiley & Sons, New York (1982).Google Scholar
- Sato, S., “Factors Influencing the Yield of Stoichiometric Water Photocatalysis over Platinized TiO2”,New J. Chem.,12, 859 (1988).Google Scholar
- Schiavello, M., “Photocatalysis and Environment: Trends and Applications”, Kluwer Academic Publishers, Dordrecht (1988).Google Scholar
- Schwarzenbach, G. and Fischer, A., “Die Acidität der Sulfane und die Zusammensetzung wässeriger Polysulfidlösungen”,Helv. Chem. Acta,43, 3329 (1960).Google Scholar