2009 Volume 77 Issue 10 Pages 862-864
Photovoltaic conversion using photosynthesis organ Grana from Spinach adsorbed nanocrystalline TiO2 layer onto ITO glass (OTE) electrode (Grana/TiO2 electrode) is developed. The shape of absorption spectrum of the Grana/TiO2 electrode is almost the same that of Grana solution. Absorption maxima of Grana/TiO2 electrode are observed at 450, 480 and 680 nm attributed to carotenoid and chlorophyll molecules. This result suggests that Grana are adsorbed onto nanocrystalline TiO2 layer onto OTE. The photocurrent responses of Grana/TiO2 electrodes are measured using acetonitrile with 0.1 mol dm−3 tetrabutylammonium hexafluorophospate as a redox electrolyte in the presence and absence of water with 100 mWcm−2 irradiation. Photocurrent of Grana/TiO2 electrode increases using the redox electrolyte containing water. Moreover, the photocurrent responses of Grana/TiO2 electrodes with monochromatic light (680 nm attributed to absorption band of photosystem II with oxygen evolved complex) irradiation are measured using acetonitrile with 0.1 mol dm−3 tetrabutylammonium hexafluorophospate as a redox electrolyte in the presence and absence of water. Photocurrent of Grana/TiO2 electrode using the redox electrolyte containing water only is observed, indicating that the evolved oxygen from water with photosystem II in Grana onto nanocrystalline TiO2 layer electrode by 680 nm irradiation is reduced to water with catalytic activity of platinum electrode.
