Masaharu Satoh

Dependences of electrical and mechanical properties of conducting polypyrrole films on conditions of electrochemical polymerization in an aqueous medium

Abstract Electrical and mechanical properties of polypyrrole films prepared under various polymerization conditions are studied. The electrical conductivity is found to be increased to higher than 500 S/cm by selecting the polymerization conditions.

A highly conducting poly (p-Phenylene) film

Polymerisation electrolytique du benzene et du diphenyle en solution electrolytique de benzonitrile contenant CuCl 2 et LiBF 4 . Conductivite electrique superieure a 100 s/cm

Electrical and optical properties of poly(p-phenylene) film and their doping effect

Poly( p -phenylene) films with a conductivity of ca . 100 S/cm are synthesized by a new method of electrical oxidation of benzene using the composite electrolytes of CuCl 2 /LiAsF 6 . An in situ study of the absorption spectra of the poly( p -phenylene) films during the electrochemical doping with AsF 6 has been carried out. From the absorption spectrum of undoped state, we find a strong absorption peak at ca . 3.4 eV which is associated with the transition from ground-state to excited-state. The remarkable changes of the absorption spectra below the photon energy of 3.0 eV are observed, which are related to the polaron and/or bipolaron states of this polymer. The electrochemical n -type doping is also demonstrated.

Highly Conducting Polypyrrole Prepared by Electrochemical Oxidation Method in Aqueous Solution

Conducting polypyrrole films with electrical conductivity higher than 400 S/cm have been prepared by the simple electrochemical oxidation method in aqueous solution with high electrolyte concentration. It has been also found that the conventional surfactants can be used successfully to prepare the high quality polypyrrole film.

Electrochemical preparation of poly(p-phenylene) and poly(naphthylene) films

Abstract A new method of electrochemical polymerization of aromatic compounds has been proposed for obtaining the conducting polymer films. The improved electrochemical polymerization of benzene utilizing the composite electrolytes of CuCl 2 /LiAsF 6 gives a poly(p-phenylene) film of structural integrity comparable to poly(acetylene). This polymer film shows the conductivity of more than 100 S/cm and has a quite smooth surface with outstanding properties of thermal stability. Conducting poly(naphthylene) and poly(anthracene) films have also been prepared by the similar electrochemical polymerization of naphthalene and anthracene. These films demonstrate the reproducible doping and undoping with electrochemical and chemical means.

Electrochemical n-type doping of poly(p-phenylene) film

The authors have succeeded in preparing flexible poly(p-phenylene) film by means of an improved method for electrochemical polymerisation of benzene. Evidence for electrochemical n-type doping of this polymer is obtained from simultaneous measurements of a cyclic voltammogram and absorption spectra. Although the polaron and/or bi-polaron levels in the gap states appear on n-type doping, the levels demonstrate an anomalous shift to the band edge. The electronic band scheme of poly(p-phenylene) film is discussed in comparison with those of other conducting polymers.

Characteristics of Rechargeable Battery Using Conducting Poly(p-phenylene) Film

A secondary battery utilizing electrochemically prepared poly(p-phenylene) film as cathode material in an electrolyte of LiAsF6/propylenecarbonate with Li anode was studied. A high cell voltage of 4.1 V and energy density of 300 Wh/kg (based on the weight of electroactive materials) were obtained. The cell demonstrates excellent discharge characteristics under the extremely large discharge rate of 2.5 kA/kg with an energy efficiency of more than 85%.

Enhancement of electrical conductivity of poly( p‐phenylene) and polynaphthylene films by heat treatment

Electrical conductivity of poly(p‐phenylene) and polynaphthylene films increases by many orders of magnitude by the heat treatment at temperatures between 400 and 1000 °C, which is interpreted in terms of the carbonization. A linear temperature dependence of thermoelectric power also supports this interpretation.

Property of Conducting Polypyridazine Film Prepared by Electrochemical Method

Polypyridazine films with electrical conductivity as high as 6 S/cm and blue in color have been prepared by the electrochemical oxidation of pyridazine monomer for the first time. Reducing the as-grown film by electrochemical or chemical means, a semiconducting film with optical absorption edge of 1.8 eV and a brown color is obtained.

Electrochemistry preparation of high quality poly(p-phenylene) film

A high quality poly(p-phenylene) film which is green in colour, with an electrical conductivity of ca. 100 S/cm, has been obtained by the electrochemical polymerization of benzene.