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We investigated the field emission properties of single-wall carbon-nanotube (CNT)-dispersed conducting polymer thin film prepared by spin coating and electrophoresis. A p-type conducting polymer such as poly(3-octylthiophene) (P3OT) or poly(2methoxy, 5-(2 0 -ethyl-hexyloxy)-p-phenylenevinylene) (MEHPPV) doped with CNTs is an excellent field emitter. The field emission was successfully reproduced by an electrophoretic technique and the turn-on fields of CNT-dispersed P3OT films were 4-6 V/mm. Moreover, the field emission properties were markedly improved by post-field treatment on a thermally oxidized Si wafer, and a low turn-on field of 1.6 V/mm was successfully obtained probably due to the improved vertical orientation of CNTs. New devices having both photovoltaic and field emission properties were also demonstrated. We also investigated the photovoltaic properties of the devices composed of ITO/TiO 2 /CNT-MEHPPV composite/Au structure. The open-circuit voltage V OC and short-circuit current density I SC of the device without CNTs were 0.6 V and 0.4 mA/cm 2 , respectively, under 100 mW/cm 2 white light illumination. Although V OC and I SC were not considerably improved, a marked increase in current density, more than a factor of 1000 at À1 V, was obtained for the device with a CNT-dispersed MEH-PPV layer. Such an increase in current density was obtained only in negative biasing on the Au top electrode and we attributed this increase to the field emission of electrons from CNTs into the TiO 2 layer.

A new organozinc compound, zinc bis-2-(o-hydroxyphenyl)benzoxazolate, was prepared from 2-(o-hydroxyphenyl)benzoxazole and electroluminescent properties of the compound was investigated. An electroluminescent device was composed of glass substrate/indium-tin-oxide/hole transporting layer/zinc benzoxazolate/Al thin films. The electroluminescence of blue light was observed with the electric field of over 90 MV/m.

The Garton effect has been observed in PET films in the low-frequency range from 0.0003 to 0.1 Hz. The current wave manifests a remarkable deformation which depends on the temperature, the applied voltage, the frequency and the sample thickness. Tan delta evaluated from the power loss decreases with the increase in applied voltage. A model based on the electrode polarisation has been proposed to explain the experimental results such as the deformation of the current wave and the magnitude of tan delta . The activation energy of the mobility of carriers has been evaluated to be approximately 1.5 eV.

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