| Recently organic optoelectronic devices have attracted intensive interest among scientists and technologists because of their huge market and intriguing potential applications. Among these devices, organic photoconductor (OPC) drum is the only one who has been put into market in large scale. At present, because scientific research and fabrication techniques of double-layered OPC drum are considerable mature, more and more attention has been paid to single-layered OPC drum for its simple structure and low cost. In the thesis, we aim to design a new kind of single-layered photoconductor with high performance, to study the relationship between aggregate state structure and photoconductivity, and to enrich organic semiconductive theory system.In the first chapter of the dissertation, we review the development history and the trend of xerography technology, present a series of organic semiconductive materials and their device structures, and bring forward three ways to prepare single-layered photoconductor with high performance by dimixing, preparing nanomaterials, and synthesizing new organic electron transport materials. The methods used to prepare nanostructure phthalocyanines are introduced. It is found that the quantum scale effect in organic nanostructures is the real reason for the unique photoconductive properties. The recent development of organic electron transport materials are reviewed as well. Several technologies for charge carrier mobility measurement are summarized and compared, and a series of basic principles for designing high-performance organic electron transport materials are suggested as well.In the second chapter, a single-layered photoconductor was made incorporating oxotitanium phthalocyanine/ chloroindium phthalocyanine (InClPc/TiOPc) composite as charge generation material (COM) into polymer matrix. The negative photoconductivity effect was found in the dimixing phthalocyanine composites. The experiment results indicated that the negative photoconductivity effects were closely related with the partial charge transfer from the center metals to phthalocyanine rings, and the separation efficiency of photocarriers was a key factor to thephotoconductivity.In the third chapter, the organic single-layered photoreceptors were prepared, which consisted of polycarbonate matrix containing dispersed N,N'-diethyl-4-aminobenzaldehyde-l-phenyl-l'-(a-naphthyl)-hydrazone (BAH) and 2,4,7-trinitryl-fluorenone (TNF) as bipolar charge transport materials (CTM), as well as TiOPc as charge generation material (COM). The influence of organic electron transport material on the photosensitivity in the photoreceptors was investigated. It was found that small amount of TNF (TNF/BAH<0.005) could improve the photosensitivity of photoreceptors greatly, i.e., the enhanced photoconductive effect, but the further increase of TNF concentration would lead to the decline of the photosensitivity. DSC, UV-Vis and cyclic voltammograms studies showed that the enhanced photoconductivity might be resulted from the improvement of the separation efficiency of charge-carrier pairs, and that the decline of photosensitivity was due to the formation of the charge transfer complex of TNF-BAH. The enhanced photoconductive effect from small amount of TNF facilitates the preparations of new organic photoconductive devices under the drive of low fields.In the fourth chapter, InClPc nanoparticles embedded in poly(N-vinylcarbzaole) (PVK) were prepared successfully by dissolving InClPc in aprotic organic solvent/Lewis acid with great concentration for the formation of electron donor-acceptor complexes, i.e., the method of complexation-mediated solubilization. The fabricated InClPc nanoparticles were characterized by means of UV/Vis absorption, X-ray diffraction pattern, and TEM. The results showed that InClPc nanoparticles were ball-shaped with a size of 25-50 run, that their diffraction peaks become broader, and that the blue-shift in UV/VIS absorption was also observed. The photoconductivity of InClPc nanoparticles in single-...
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