Heishoku An

Photoconductive properties of TiO2 films prepared by the sol–gel method and its application

The Photoconductive characteristics of TiO2 films prepared by the sol-gel method, and the photovoltaic characteristics fabricated with the resulting TiO2 film and phthalocyanine nickel (NiPc) are investigated. For a TiO2 film with hydroxypropyl cellulose (Hpc) heat treated at 500°C for 10 min, the relative sensitivity is about ten times higher than that without Hpc. A space-charge-limited current is observed in the dark current–voltage characteristic of the TiO2 film with Hpc. It is found that the TiO2 film with Hpc has a photosensitizing effect. The photovoltaic characteristics of TiO2(Hpc)/NiPc are as follows: the short-circuit current density, Jsc is 5.6×10-7 A cm-2, the open-circuit voltage, Voc is 0.24 V, the fill factor (F.F) is 0.64 and the power conversion efficiency, η is 0.73. Furthermore, the carrier transport mechanisms of the TiO2(Hpc)/NiPc photovoltaic cell are discussed.

Electrochemical copolymerization of benzo[b]thiophene

Abstract Highly conducting polymer films that are stable to ambient conditions and have good mechanical properties can be obtained by the electrochemical copolymerization of benzo[b]thiophene with pyrrole if a suitable supporting electrolyte, solvent, current density and copolymer composition are selected.

Electrochemical polymerization of methyl-substituted quinolines

Abstract Of the quinoline derivatives, only the 4-methyl-quinoline formed a polymeric film by electrochemical polymerization using acetonitrile as solvent and LiClO 4 or TBA(ClO 4 ) as supporting electrolyte. The film has good mechanical properties, and its conductivity was 10 −3 −10 −5 S cm −1 .

Junction characteristics of polybenzo[b]thiophene

Abstract The junction characteristics of BF 4 − -doped polybenzo[ b ]thiophene with indium have been studied using sandwich-type elements. The BF 4 − -doped polybenzo[ b ]thiophene gave rectifying contacts for indium and ohmic contacts for gold. The analyses of the current-voltage and the capacitance-voltage characteristics have revealed that a Schottky barrier is formed at the interface between the polybenzo[ b ]thiophene and indium. However, the ideality factor of the barrier is large and the junction is imperfect.

The junction properties of the anionic surfactant doped polypyrrole with indium.

Summary form only given. Electrochemical polymerization of pyrrole was carried out in anionic surfactant aqueous solutions, and the Junction Characteristics of anionic surfactant doped polypyrrole with injium have been studied using sandwich devices. It has been observed that the Au/polypyrrole/In diode has unsymmetric, non-ohmic rectifying Characteristics. The analyses of the current-voltage and the capacitance-voltage characteristics have revealed that a Schttky barrier is formed between polypyrrole and indium.

Electrochromism of the Composite Film of Ethylene-Vinyl Alcohol Copolymer and Polypyrrole

Abstract The composite film of ethylene-vinyl alcohol copolymer (EVOH) and polypyrrole (PPy) were prepared by the electrochemical polymerization of pyrrole on an EVOH film containing lithium perchlorate coated on Indium-tin oxide (ITO). When a potential was varied from −1.0 V to 1.0 V, the color of the composite film changed reversibly from yellow to brown. The difference in absorbance (ΔA, 0.1—0.15) at 800 nm between the application of 1.0 V and −1.0 V in UV/VIS spectra of the composite film did not exhibit a pronounced decrease until ca.7000 cycles. In contrast to this behavior, the ΔA of a single PPy film rapidly dropped with an increasing cycle number and approached 0 within ca. 1000 cycles. This result indicates that the durability against the repeated application of potentials markedly improved in the composite film.

Junction properties of ClO4−-doped poly(methylquinoline) with indium

Abstract Junction properties of ClO − 4 -doped poly(4-methylquinoline) with indium are investigated using a sandwich-type element. ClO − 4 -doped poly(4-methylquinoline) and indium form rectification contacts, whereas ohmic contacts are formed for junctions with gold or platinum. From analyses of current-voltage and capacitance-voltage characteristics, we suggest that a Schottky barrier is formed at the interface between poly(4-methylquinolene) and indium.