| With the development and advancement of nanotechnology, nano-material became indispensable in the present society because of the unique property and application compared to traditional material. Among preparation methods, electrospinning as a newly developed technique has attracted greet attention from researchers. However, with the development of electrospinning technique and society, simplex nanofiber cannot meet the need of reality. Inorganic/organic nanocomposites which have wild applications in electronics, medicine, catalyze, environmental protection etc., are the hotspot in material research. But excellent property often requires a uniform size and homogeneous distribution throughout a suitable substrate. So control over agglomeration is a key point in the preparation of particles.In the second chapter of this dissertation, electrospinning technique is employed to fabricate PAN nanocomposite film. We analyzed the effect of concentration of precursor to the morphology of nano-products, observed the process from nanoparticle to nanofiber according to the increasing of the solution concentration. Furthermore, PAN nanofiber with uniform diameter was surface modified to obtain amidoxime group, which has the ability to adsorb metal nanoparticles. Finally, Ag/PAN, Pd/PAN nanocomposite film was prepared. The combinative method between nanoparticles and PAN nanofiber has been discussed in this chapter. We find that almost all of the nanoparticles were attached on the surface through chelating effect. This method will be propitious to prevent nanoparticles from aggregation. Further more, we examined the ability of these nanocomposite films to promote the reduction reaction of methylene blue (MB) dye and Heck reaction respectively. They have excellent catalyze properties, and easy for catalyst recovery and recycle also.In the third chapter of this dissertation, we fabricate three kind of inorganic nanoparticles (Ag2S, CuS, PbS) on the surface of PAN nanofiber by combining electrospinning and gas-solid reaction. Investigate the formation, distribution and visible light photocatalytic activity of inorganic nanoparticles.The focus of the fourth chapter has been on fabrication of inorganic/organic nanofiber film with adsorption and photocatalytic degradation simultaneous. ZnO-SnO2/β-CD/PAN-co-AA nanocomopsite film is obtained via electrospinning combined with chemical modification, high temperature carbonization, simple doping and so on. It finds that adsorption has positive role for the efficiency of this photocatalyst. ZnO-SnO2/β-CD/PAN-co-AA nanocomopsite film showed much higher adsorption and catalyzes ability to elimination of MB than ZnO-SnO2 nano-heterostructure.In the fifth chapter of this dissertation, we improve the traditional electrospinning technique to employ a multi-nozzle electrospinning setup. Nanofiber from the one nozzle and micro-sized fiber from the other nozzle were combined homogeneously by two-nozzle electrospinning. Microfiber plays the role of support which is favorable for enhancing the mechanic performance of the film. As a result, the weak intensity problem of membrane is effectively resolved by this advanced electrospinning technique. The result shows compared with film composed by simplex nanofiber, the tensile strength of the composite fiber film contain nanofiber and microfiber simultaneity has been enhanced by a factor of 4.54. After further improve orientation of composite fiber, the tensile strength is 30.00 times that of simplex nanofiber. Furthermore, this technique has been used to prepare pH-sensitive films with enhanced mechanical property. The results show that the pH sensitive film that merely consist with PAN nanofiber or composite PAN/PA-6 fiber all exhibited remarkable color change from pale yellow to violet in a wide range of alkaline solutions and rapid response time within 100 S. But after microfibers added, the tensile strength of mat was enhanced from 1.30 MPa to 6.90 MPa prominently which is beneficial to put the mats into practice.
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