2.3. Solar cell fabrication
After surface treatment, the electrodes were sensitized overnight in 0.5 mM (Bu4N)2-[Ru(4,4-(COOH)-2,20-bipyridi-ne)2(NCS)2] (N719) in ethanol solution. A 50 mm hot melt sealing foil (Surlyn) was sandwiched between the electrode and a platinized FTO with two open pores. The electrolyte, consisting of 0.3 M DMPII, 0.5 M LiI, 0.05 M I2, and 0.4 M 4-TBP in methoxypropionitrile, was injected from the side of the electrodes.