Photoconduction conductive polymers

Kazaoui S, Minami N, Nalini B, Kim Y, Hara K (2005) Near-infrared photoconductive and photovoltaic devices using single-wall carbon nanotubes in conductive polymer films. J Appl Phys 98 084314... 

Whatever the precise mechanisms of conduction, the macroscopic conductivity observed in any conducting polymer will depend strongly on the morphology of the sample and on whether it is oriented and, if so, to what degree, because these factors will influence both intra- and inter-chain mobility. For these reasons the conductivities of samples prepared under very similar conditions may differ considerably. The above account has merely attempted to indicate some of the types of process that may be involved in conduction in these relatively new materials, for which it is certain that no single mechanism can explain all the experimental results. Even when a particular theoretical description fits the conductivity, it cannot be accepted as the correct mechanism unless it can also accoimt for the observations of magnetic susceptibility, thermo-electric power, photoconductivity and other properties. 

Typical examples of photoconductive polymers (group (b)) are listed in Table 2.2. Concerning the field of conducting polymers, including photoconducting polymers, the reader is referred to various books and reviews [1-21]. 

It is possible to make inert polymers photoconductive and to improve the photoconduction performance of conducting polymers by doping, i.e. by the addition of appropriate low molar mass substances to the polymers. Relevant work has been reviewed by Mylnikov [3]. Early studies with inert polymers such as poly-... 

Similarly, because photoconductivity is essential to photorefraction, readers may refer to Conductive Polymer Composites. 

Since the photoconductive properties of poly(A-vinylcarbazole) (PVK) were revealed, carbazole-based polymeric materials have been extensively studied [264-266]. Recently, there has been a renewed interest in the study of photo-conductive polymer composites. Photoactive dopants capable of charge injection into the polymer matrix are normally employed. Of these photoactive dopants, C60 and CNTs as well as inorganic SCs have been shown to be among the most efficient to date [267]. 

The organic active layer is a blend of a conductive polymer (acting as electron donor) and an electron acceptor characterized by an organic moiety. Indeed, fullerene derivatives showed suitable electronic properties for this role. The most conunonly used polymers for solar cells are P3HT (poly(3-hexylthiophene)), but other copolymers bearing thiophene units have also been studied to build plastic solar cells with higher photoconductivity. ... 

C. H. Lee, et al.. Large enhancement of the transient and steady-state photoconductivity of conducting polymer/Cao composite films, Svnth. Met. 70 1353 (1995). 

Polyhexylthiophene 21, one of well-known conducting polymers, can form mesoscopic two-dimensional patterns on solid surfaces by also using the simple casting method. The mesoscopic stripe prepared from chloroform solution is expected to be a supramolecular cord because several hundred polymer chains are tied up in a bundle. To measure the photoconductivity of the single bundle one side of the stripe is contacted with an Ag-paste electrode and another side is contacted... 

Roth, S., "Conductive polymers in molecular electronics Conductivity and photoconductivity", p. 129 in Salaneck, W.R. Clark, D.T. Samuelsen, E.J. (Eds.), Science and Applications of Conducting Polymers, Adam Hilger, New York, USA (1991). 

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