| The recent progresses in preparation and applications of carbon nanotube (CNT)/organic semiconductor hybrids were summarized in Chapter 1. The potential application of the hybrids in the near-infrared (NIR) detection was introduced. The performance of optoelectronic devices depends heavily on their excited state property, which mainly involves charge carrier generation, separation, and transportation. The optimal performance can be obtained via designing of molecular structure and modulating of aggregated structure. In this dissertation, three approaches, from blend, encapsulation and enrobe, to electrochemical deposition, were carried out to fabricate high photosensitive CNT/phthalocyanine hybrids in the light of molecular and material designs. The optoelcteronic property of the hybrids was investigated in detail as well.The multi-wall carbon nanotubes (MWCNT) bonded with dodecylamine groups were obtained by chemical modification. The modified CNT showed improved solubility in organic solvents and miscibility with polymer matrix. The photoconductivity of oxotitanium phthalocyanine (TiOPc) doped with modified CNT was investigated by the xerographic photoinduced discharge method. The results showed that the photosensitivity of the dual-layer photoreceptor (P/R) with modified CNT/TiOPc composite as charge generation material was higher than that with pristine TiOPc, and increased with increasing the content of modified CNT in the composites. The optimal performance was obtained when the weight ratio of doped CNT was 6% and a high (E1/2)-1 of 10 J-1cm2 was obtained at 570 nm, nearly 5 times higher than that of pristine TiOPc at the same wavelength. It was explained that, as demonstrated by XPS, after doping with modified CNT, the intramolecular charge transfer occurred in TiOPc and the charge transfer exciton was prone to be produced, which was favorable to charge carrier generation. The efficiency of charge carrier separation increased as well due to the photoinduced charge transfer from TiOPc to CNT, which might also contribute to the improved photosensitivity of the modified CNT/TiOPc composites.To facilitate the photoinduced charge transfer, the fabrication of one-dimensional (1 D) CNT/rare earth biphthalocyanine hybrid materials with large interfacial area wasexploit. The erbium biphthalocyanine (ErPc2) nanorods or nanowires were encapsulated in the cavities of CNT by a capillary filling method. The length and the diameter of the ErPci nanowires can be easily tailored by the CNT mold, capillary filling time, and the concentration of ErPc2. The CNT/ErPc2 hybrid materials exhibit photoresponse at the NIR region. CNT templated assembly of ErPc2 nanowires was performed by the phase separation (coacervation) method. The length and the diameter of the nanowires can be easily tailored by the nanotube template and the concentration of ErPc2. The photoconductivity of the CNT wrapped with ErPc2 nanowires was investigated. The dual-layer photoreceptors with CNT/ErPc2 hybrid materials as charge generation materials exhibited enhanced photosensitivity compared to that with pristine ErPc2. At 762.5 nm, a high (E1/2)-1 of 0.833 J-1cm2 was obtained, more than 4 times higher than that of pristine ErPc2. The improved photosensitivity was contributed from the photoinduced charge transfer from ErPc2 to CNT. Combining the optic, electronic, and magnetic properties of rare earth phthalocyanines and CNT, the 1 D hybrid materials are expected to have versatile potential applications in optoelectronic devices.Gadolinium biphthalocyanine (GdPc2) and ErPc2 thin films were prepared by vacuum deposition at various substrate temperatures. The effects of substrate temperature and film thickness on the film morphology, crystalline structure, and optical absorption were studied. The ErPc2 and GdPc2 films exhibited fine-grain morphology and small degree of crystallization at low substrate temperature. The size of the crystallites was enlarged when the film thickness increases. If the substrate temperature was elevated to 100, the ErPc2...
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