Showing papers on "Organic semiconductor published in 1980"

Organic semiconductor electrophotographic material

Abstract: PURPOSE:To obtain an electrophotographic material having high sensitivity, heat resistance, light resistance, and high transparency for ultraviolet rays, and high stability, by adding a specified bis-(4-N,N-dibenzylamino-2-substituted phenyl)alkane derivative to a photoconductive layer. CONSTITUTION:A photoconductive layer containing one or more organic semiconductors represented by the formula (R1, R2 are H or lower alkyl; R3 is CH3, C2H5, OCH3, OC2H5; and R4 is H, CH3, NO2, or halogen) is formed on a conductive substrate. The above compound is dissolved or suspended in a solvent, when needed, with a chemical sensitizer, a spectral sensitizer, or the like added, and this fluid is coated and dried on the conductive substrate to form an electrophotographic receptor. The above compound is soluble in a solvent low in cost and toxicity, such as toluene, and can produce a photoreceptor capable of forming always sharp copied images, and being used repeatedly, without using a poisonous inorganic semiconductor, such as Se.

Energy gaps in organic semiconductors derived from electrochemical data

Abstract: The band gap, EG, of an organic solid can be estimated by adding the magnitudes of oxidation and reduction potentials of the compound in solution, plus a correction to the ion solvation energy which allows for the different dielectric constants of solvent and solid. Values of EG for 30 organic solids have been estimated. The auto-ionization model, previously used for aromatic hydrocarbons, is applied to dyes and chlorophylls. The values of EG are used to interpret various existing results on photoconduction and semiconduction in dyes and chlorophylls.

Electron acceptor surface states due to oxygen adsorption on metal phthalocyanine films

Abstract: The dependence of the surface photovoltage of NiPc and CuPc films on oxygen ambient has been measured, and the observed effects can be quantitatively accounted for with a theoretical model which involves the transfer of charge from the Pc ring to the adsorbed O2 and the formation of a Pcδ+–Oδ−2 species at the surface of the Pc film. Symmetry arguments based on a simple bonding model are used to explain the nature of these O2 electron acceptor surface states. Charge transfer complexes such as this are important both to the doping of these organic semiconductors, and to a fundamental understanding of the oxidations photocatalyzed by these porphyrinlike materials which are closely related to some of the processes which occur during photosynthesis.

Electrical conductivity of SbF5 doped polyacetylene

Abstract: Conductivity measurements are reported for polyacetylene films with various SbFS doping concentration. The activation energy behaviour is deduced and compared with previous results obtained with iodine and AsF5 doping. The results are discussed in terms of a qualitative model of the dopant ordening in the system.

The surface photovoltage of polymethine semiconducting films

Abstract: Recent solar cell work on Al/merocyanine/Ag sandwich devices has prompted the examination of the surface photovoltage of thin films (∼500 A) of merocyanine and of four other closely related polymethine type dyes deposited on Ag rear contacts. All of these materials exhibited space charge depletion layers at the front surface with energy band bending changes resulting from a laser pulse ranging from 1 to 100 mV, and corresponding photovoltaic relaxation time constants on the order of 30 msec. The spectral dependence of the observed photovoltage was dominated by the nominally ’’forbidden’’ S0→T1 transition in the near IR. Much less photovoltage is observed at wavelengths corresponding to the allowed S0→S1 transition, even though light of this photon energy is strongly absorbed. This discrepancy between the relative intensity in the absorption and photovoltage spectra could be due to decreased dissociation of the bound excitons, and/or to increased recombination of the free carriers at the organic semiconduc...

Process for preparing highly conductive acetylene high polymer

Abstract: A process for preparing organic semiconductor, which comprises doping an acetylene high polymer having a fibril structure with a specific electron-accepting compound. Conventional electron-accepting compounds are highly toxic and provide conductive acetylene high polymers which do not always exhibit a sufficiently high electric conductivity, which have a mechanical strength seriously reduced by the doping, and which have an insufficient heat resistance. The use of a specific, the low-toxic electron-accepting compound of the present invention provides a conductive acetylene high polymer having an enhanced electric conductivity and good flexibility and heat resistance. This conductive acetylene high polymer is a p-type semiconductor enabling to freely control the electric conductivity within the range of 10-9 to 103(Alpha)-1(Alpha)cm-1 and is useful as a material for conductive materials, p-n heterojunction elements, and photo-electric transducers such as solar batteries, photosensors, etc.

Doped polyacetylenes and their production

Abstract: Doped acetylene polymers are produced by immersing an acetylene polymer under an inert gas atmosphere in an organic solvent solution of a dopant selected from the group consisting of a platinum group metal complex, a carbonium salt, an oxonium salt and a parabenzoquinone derivative. According to this process, a doped acetylene polymer having any desired electrical conductivity can be produced and the doped acetylene polymer thus obtained has excellent properties as an organic semiconductor material for solar batteries, various sensors, etc.

I‐V and C‐V characteristics of Cr∥H‐Pc∥ Cr organic sandwich cell

Abstract: The measurement of the capacitance of a thin‐film organic semiconductor sandwich by the capacitor discharge technique and by the quasistatic technique is considered. It is suggested that the apparent voltage dependence of the capacitance is due to charge injection and transport and is not directly related to barrier formation. Data obtained on Cr ∥ phthalocyanine ∥ Cr sandwiches are in good agreement with this model.