Organic-metallic hybrid polymers are formed by the complexation of metal ions with organic modules bearing two coordination sites. The hybrid polymers consisting of bis-terpyridines and metal ions such as Fe(II) or Ru(II) have a specific color based on the metal-to-ligand charge transfer (MLCT) absorption. Cyclic voltammograms of the polymers exhibit a reversible redox wave according to the redox reaction of the metal ions. Interestingly, a polymer film cast on an indium tin oxide (ITO) electrode exhibits excellent electrochromic properties; the color of the film disappears when a higher potential as compares to the redox potential of the metal ions is applied to the polymer film. In addition, multicolor electrochromic changes appear on introducing two types of metal ions to the polymer. Electrochromic solid-state devices are successfully fabricated by using these polymers. Keywords Organic-metallic hybrid polymers Á Self-assembly Á Electrochromic properties Á Electronic solid-state devices This paper is dedicated to Professor Takakazu Yamamoto in honor of his pioneering research efforts and accomplishments in the fields of organometallics and p-conjugated polymers.

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Photovoltaic (PV) devices using blend films of poly(methyl phenyl silane) (PMPS) and fullerene (C60) are fabricated, and the effects of various technical parameters during device fabrication on the PV characteristics under AM 1.5G simulated solar light illumination of 100 mW/cm2 intensity are investigated. The PV performance of the devices depends on the mixing ratio of PMPS:C60, the kind of buffer layer, the thickness of the buffer layer, and the thermal annealing temperature of the devices. The devices optimized for the mixing ratio, kind of buffer layer, and thermal annealing temperature exhibit a short-circuit current density (J SC) of 2.26 mA/cm2, an open circuit voltage (V OC) of 0.71 V, a fill factor (FF) of 0.35, and a power conversion efficiency (PCE) of 0.57%.

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C 60 nanowhiskers (C 60 NWs) were synthesized by liquid-liquid interfacial precipitation method (LLIP method), using m-xylene as a good solvent solution of C 60 and isopropyl alcohol (IPA) as a poor solvent of C 60 . The growth mechanism of C 60 NWs was investigated by the long-term observations using optical microscopy. In the early stage of growth, C 60 NWs grew faster and longer at 5°C than at 20°C. However as the growth time became longer, the growth rate of C 60 NWs became greater at 20°C than at 5 °C, and the longer C 60 NWs were obtained at 20°C than at 5 °C. Further, it is suggested that the growth of C 60 NWs proceeds by repeating the dissolution and reprecipitation process of C 60 NWs.