Dark- and photoconductivity

The dark- and photoconductivity of organic compounds has long been regarded as a sort of side-effect arising from impurities, ionic carriers, or traces of adsorbed water. 

It is now known that dark- and photoconductivity is connected with the structure of organic compounds 10>. The conductivity of organic dyes and other organic compounds, like that of inorganic semiconductors, is attributable to electronic charge carriers, i.e. electrons and positive holes. The dark conductivity [Pg.87]

The significance of the interplay of the elementary processes (generation, transport, and recombination) for dark- and photoconductivity is discussed below. 

In the course of experiments on the dark- and photoconductivity of dyes a series of industrially interesting effects have been noted. Some examples are given below for further details, see 10>12 88> for the fundamentals of the different effects, see Section II. 

Meier, H. Organic Semiconductors dark- and photoconductivity of organic solids. 

H. Meier, Organic Semiconductors Dark and Photoconductivity of Organic Solids, Verlag Chemie, Weinheim, Germany, 1974. 

Gntman, F. and Lyons, L. E., Organic semiconductors, John Wiley, New York, 1967. Meier, H., Organic semiconductors Dark- and photoconductivity of organic solids, Verlag Chemie, Weinheim, 1974. 

In the following we describe the technique used at Jiilich for combined measurements of thermopower and dark- and photoconductivity. A cryostat is employed having two cold fingers that can be cooled independently by insertion of liquid nitrogen or by a flow of cool Nj or air. Each cold finger bears a 100-W resistance heater (HI and H2 in Fig. 5a). The heater mass... 

Plastoquinones perform the same role in the photosynthetic apparatus of plants as ubiquinone does in the mitochondrial membrane. Masters and Mauzerall122 used a bilayer lipid membrane made of egg lecithin containing chlorophyll a in order to elucidate the effect of plastoquinones PQ5 and PQ9 on photopotential. The addition of plastoquinones increases the dark and photoconductivities about 20 times. 

Damodare, L., T. Soga, and T. Mieno. 2003. Studies on dark and photoconductivities of poly [2-methoxy,5-(2 ethylhexyloxy)-p-phenylene vinylene] C6o thin films. pn J Appl Phys 42 2498. 

Narasimharaghavan, P K. Yadav, H. O. Varadarajan, T. S. Patnaik, L. N. Das, S. Organic photoconductors dark and photoconduction studies in two /)-dimethylamino styryl dyes derived from pyridine-2 and pyridine-4. J. Mater. Sci. 1991, 26, 4774-4786. 

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