Two polypyridyl ruthenium complexes, bis[4-(N,N'-diphenylamino)phenyl-2,2':6',2 `'-terpyridine]ruthenium(II) (1) and bis[4'-(4-\2-[-(N,N'-diphenylamino)phenyl]ethylene\phenyl)-2, 2':6',2 `'-terpyridine]uthenium(II) (2), have been synthesized. They possess an extended conjugation and strongly coupled electronic states. The features of these compounds were carefully studied from several respects. Steady-state spectroscopy showed that the two compounds had strong excitation dependent emission behaviors caused by mixing features of different electronic states. Femtosecond fluorescence upconversion spectroscopy was also used to investigate the fluorescence dynamics of the compounds. An ultrafast relaxation time of similar to 100 fs of the (MLCT)-M-1 (metal-to-ligand charge-transfer) states, which may originate from an ultrafast intersystem crossing to form (MLCT)-M-3 states, was found in both samples. However, thermal populated states and vibration associated excited state interactions were suggested for 1 with excitation at wavelengths below 400 nm, whereas vibrational energy redistribution with a time scale of few picoseconds was observed in the extended conjugated system of 2. These compounds will have potential application in both artificial photosynthesis systems and photovoltaic devices.

Poly(3-hexylthiophene) (P3HT):1-(3-methoxycarbonyl)-propyl-1-Phenyl-(6,6)C-61 (PCBM) photovoltaic devices based on ordinary paper as substrate were fabricated. Au layer deposited on paper by RF magnetron sputtering was used as anode. The hybrid layer of LiF co-evaporated with Al was used for transparent cathode, and the light transmittance could reach to similar to 70%. By optimizing the mass proportion of LiF and Al, we could get the best papery solar cells with the short current density and open circuit voltage 0.1 mA/cm(2) and 0.39 V. respectively. The corresponding power conversion efficiency was measured to be 0.13 parts per thousand illuminated with 100 mW/cm(2) air mass 1.5 global (AM 1.5 G) simulated sunlight. (C) 2010 Elsevier B.V. All rights reserved.