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  1. The chief thrust of the research has been directed towards the evaluation of polyacetylene (CH)/sub x/, the prototype conducting polymer as an electrode-active material in novel, rechargeable batteries employing nonaqueous electrolytes. The p-doped material, ((CH/sup +y/)A/sub y//sup -/)/sub x/, (where A/sup -/ is an anion) in conjunction with a Li anode, shows excellent discharge characteristics, e.g., very little change in discharge voltage with change in discharge current and a high power density. Its energy density is also good but it shows poor shelf life. When (CH)/sub x/ is used as a cathode (Li anode), which results in the formation ofmore » the n-doped polymer, (Li/sub y//sup +/(CH/sup -y/))/sub x/, during discharge, good discharge plateaus and power densities are obtained together with excellent shelf life and good recyclability. The energy density is, however only moderate. Cells employing an (M/sub y//sup +/(CH/sup -y/))/sub x/ (where M = Li, Na) anode and a TiS/sub 2/ cathode show very good discharge and recycling characteristics but their energy density is poor.« less
  2. A fuel cell is described for reacting an oxidizing agent and a fuel, comprising anode means, cathode means and electrolyte, at least one of the electrodes comprising an aniline polymer; wherein the oxidizing agent comprises gaseous oxygen.
  3. Conducting polymers combine the electrical properties of metals with the advantages of plastics. Ordinary polymers have the electronic profile of insulators and semiconductors. To make polymers conduct electricity, small quantities of certain chemicals are incorporated into the polymer by a process called doping. In 1977, the first conducting polymer was synthesized; in 1981, the first battery with polymer electrodes was demonstrated. Last summer, conducting polymers matched the conductivity of copper. Conducting polymers also have interesting optical, mechanical, and chemical properties that taken together with their ability to conduct might make them effective in novel applications. 5 figs.
  4. Trans-polyacetylene, (CH)x, can be p-doped (oxidized) to the metallic regime by gaseous oxygen in the presence of an aqueous solution of a non-oxidizing acid such as HBF4. The oxygen oxidizes the (CH)x to (CH(+y))x while the HBF4 supplies a stable fluoroborate counter anion to give a species such as (CH(+y)A(-y)x. The doping process is consistent with the reduction potentials of (CH)x and O2 in acid solution. In the absence of the acid, oxygen reacts irreversibly with the semiconducting (CH)x to destroy its conductivity.
  5. A secondary battery is described comprising an anode means, a cathode means, and a electrolyte at least one of the electrode means including as an electrode active material a conjugated polymer which is characterized as having conjugated unsaturation along a main backbone chain thereof; the polymer being either oxidized or reduced to an electrically conducting state wherein it is doped with at least one ionic dopant species; the electrolyte comprising the ionic dopant species or a compound ionizable to form the ionic dopant species; the electrolyte being non-aqueous and inert with respect to the electrodes.
  6. Characteristics of various electrochemical light-emitting devices having a configuration such as, for example, Al/MEH-PPV+TBATS/ITO (where TBATS = tetrabutylammonium p-toluenesulfonate) are reported and compared with similar devices using different electrolytes and different electrode materials. Flexible, {open_quotes}completely organic{close_quotes} polymer dispersed liquid crystal light valves have been fabricated from transparent plastic substrates on which a conducting film of polypyrrole has been deposited from an aqueous solution of polymerizing pyrrole. A new concept, {open_quotes}microcontact printing{close_quotes}, is investigated for patterning polypyrrole deposited on plastic and glass substrates. The smallest polypyrrole features produced to date have {approximately}20-30 {mu}m dimensions. The electronic spectra of the polypyrrole ismore » critically dependent on the degree of hydrophilicity/hydrophobicity of the substrate surface.« less
  7. Initial studies of p-n heterojunctions formed between undoped trans-(CH)/sub x/ and n-CdS are reported. The junctions were characterized by measurements of current vs voltage (I-V), capacitance vs voltage (C-V), and photovoltaic response spectra. The results are analyzed in terms of the standard heterojunction equations. It is concluded that undoped as-grown films of trans-(CH)/sub x/ are p-type with a residual acceptor concentration of 2 x 10/sup 18/ cm/sup -3/, and that in spite of the complex fibril morphology the semiconductor properties can be inferred by treating (CH)/sub x/ as an effective homogeneous medium. Detailed studies of the photovoltaic response at energiesmore » below the energy gap for (CH)/sub x/ imply the existence of a well-defined deep trapping state in polyacetylene with an energy near the center of the gap.« less
  8. Despite great theoretical and technological interest in polyacetylene, (CH)/sub x/, the basic features of its band structure have not been unambiguously resolved. Since photoconductivity and optical absorption data have frequently been used to infer information on the band structure of semiconductors, such measurements were carried out on (CH)/sub x/. The main results of an extensive study of the photoconductivity (..delta.. sigma/sub ph/) and absorption coefficient (..cap alpha..) in (CH)/sub x/ are presented. The absence of photoconductivity in cis-(CH)/sub x/, despite the similarity in optical properties indicates that ..delta.. sigma/sub ph/ in trans-(CH)/sub x/ is induced by isomerization. It is foundmore » that isomerization generates states deep inside the gap that act as safe traps for minority carriers and thereby enhance the photoconductivity. Compensation of trans-(CH)/sub x/ with ammonia appears to decrease the number of safe traps, whereas acceptor doping increases their number. Thus, chemical doping can be used to control the photoconductive response. The energy of safe traps inside the gap is independent of the process used to generate them; indicative of an intrinsic localized defect level in trans-(CH)/sub x/. A coherent picture based on the soliton model can explain these results, including the safe trapping.« less
  9. A secondary battery is described comprising an anode means, a cathode means, and an electrolyte at least one of the electrode means including as an electrode active material a conjugated polymer which is characterized as having conjugated unsaturation along a main backbone chain thereof. The polymer is either oxidized or reduced to an electrically conducting state wherein it is doped with at least one ionic dopant species. The electrolyte comprises the ionic dopant species or a compound ionizable to form the ionic dopant species; and electrolyte is non-aqueous and inert with respect to the electrodes; wherein the conjugated polymer ismore » doped with an anionic dopant species to a p-type electrically conducting state; wherein the anionic dopant species is selected from the group consisting of halide ions, ClO/sub 4/-, PF/sub 6/-, AsF/sub 6/-, AsF/sub 4/-, SO/sub 3/CF/sub 3/-, and BF/sub 4/-.« less
  10. The potential of (CH)/sub x/ as a photosensitive material for use in solar cell applications is studied. Schottky barrier photovoltaic cells were fabricated with metallic AsF/sub 5/-doped (CH)/sub x/ on semiconducting n-Si and n-GaAs, with metallic Na-doped (CH)/sub x/ on semiconducting p-Si, with K-doped (CH)/sub x/ as an n-type semiconductor in contact with an electronegative metal (Au), and with undoped trans-(CH)/sub x/ as a p-type semiconductor in contact with electropositive metals (Na, Hg, In and Sn). The variation of barrier heights in metallic AsF/sub 5/-, PF/sub 5/-, and BF/sub 3/-doped (CH)/sub x/ in contact with n-type semiconducting Si was studied.more » p-n heterojunction solar cells were fabricated with undoped (CH)/sub x/ on ZnS. Open circuit photovoltage was 0.8 V; short circuit current was limited by series resistance. The agreement in spectral response obtained from photoconductivity and photovoltaic effect has shown that the carriers are produced in the (CH)/sub x/ and that the band gap is indeed approx. 1.5 eV. Trapping effects have been identified. Work on the construction of a (CH)/sub x/ field effect transistor is progressing. This device will be used to obtain the majority carrier mobility. (WHK)« less
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