KAWAI Tsuyoshi Osaka University Graduate School of Engineering Research Associate, 大学院・工学研究科, 助手 (40221197)
OZAKI Masanori Osaka Univeristiy Graduate School of Engineering Associate Professor, 大学院・工学研究科, 助教授 (50204186)
OHMORI Yutaka Osaka Univeristy Graduate School of Engineering Associate Professor, 大学院・工学研究科, 助教授 (50223970)
FUJII Akihiko Osaka Univerisity Graduate School of Engineering Research Associate, 大学院・工学研究科, 助手 (80304020)
|Budget Amount *help
¥42,900,000 (Direct Cost : ¥42,900,000)
Fiscal Year 1998 : ¥3,100,000 (Direct Cost : ¥3,100,000)
Fiscal Year 1997 : ¥11,000,000 (Direct Cost : ¥11,000,000)
Fiscal Year 1996 : ¥28,800,000 (Direct Cost : ¥28,800,000)
In this study, we have fabricated composites of conducting polymer and fullerene, investigated their electrical and optical properties, and realized the novel functional devices by using the composites.
In the case of doping fullerene with pi -conjugated polymer, such as poly(3-alkylthiophene), photoluminescence intensity of the composite film was quenched with increasing fullerene concentration, but the photoconductivity of the composite film was enhanced markedly depending on the fullerene concentration. These phenomena was explained by the photo-induced charge transfer between the conducting polymer and fullerene, because the fullerene plays an important role in the composite films as electron acceptors against the conducting polymers to dissociate the excitons on the polymer mainchains. Remained positive polarons on the mainchains due to the electron removal should contribute to the enhanced photocurrent.
Chemical doping of potassium into the conducting polymer-fullerene composites could be available and the low-field microwave absorption as well as the unique electron spin resonance was observed, that indicates the formation of superconducting phase in the composite of potassium-fullerene-conducting polymer. In the ESR measurement, if the excitation light is irradiated onto the composites additionally, the stable ESR signal could be observed, that coincides with that of polarons in the composites. When the organic donor materials are clqed into the composites, the unique ferromagnetic properties could be observed.
Such conducting polymer-fullerene composites, have much attractive optical, electrical, and magnetical characteristics, therefore, we emphasized that the composites should be candidates as the materials for sensors, solar cells, and superconducting devices, magnetic devices, and so on.