Photoconductivity polyvinylcarbazole

Another interesting applications area for fullerenes is based on materials that can be fabricated using fullerene-doped polymers. Polyvinylcarbazole (PVK) and other selected polymers, such as poly(paraphcnylene-vinylene) (PPV) and phenylmethylpolysilane (PMPS), doped with a mixture of Cgo and C70 have been reported to exhibit exceptionally good photoconductive properties [206, 207, 208] which may lead to the development of future polymeric photoconductive materials. Small concentrations of fullerenes (e.g., by weight) lead to charge transfer of the photo-excited electrons in the polymer to the fullerenes, thereby promoting the conduction of mobile holes in the polymer [209]. Fullerene-doped polymers also have significant potential for use in applications, such as photo-diodes, photo-voltaic devices and as photo-refractive materials. 

Recently, several photoactive polymers have been examined that fit these criteria. They include JV-polyvinylcarbazole (PVK) [101,102], (phenyl-methyljpolysilane (PMPS) [103], and amine-doped polycarbonate [104], All are known hole-transporting polymers. A large number of semiconductor nanoclusters can be doped into these polymers and interact with the polymer and facilitate carrier injection into the polymer [101-104]. Dramatic enhancement in charge generation efficiency has been observed. The availability of these semiconductor nanocluster/polymer composites opens the doorway for exploring transport-related applications. In the following sections, I review their photoconductive properties and discuss possibilities in other related areas. 

Wang reported enhanced photoconductivity in C ) mixed polyvinylcarbazole [41] and poiysilane [42]. The temperature and spectral dependences of the photoconductivity in buckminsterfullerene have been characterized with the onset of photoconductivity at 1.5 eV [43-45]. 

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