| The research of nanofibers is one of the most forefront research fields in nano science and technology, and research of macromolecule polymer nanofiber materials are also a important direction. Especially, the preparation of inorganic/organic polymer hybrid nanomaterials with the dual characteristics of the host polymer and guest incorporated object are receiving immense interest, they have broad applications in the future. Therefore, the basic research of nanofibrous-based membranes and metal nanoparticle-incorporated nanofibrous membrane has become necessary.In this present article, the polyethyleneine (PEI)/polyvinyl alcohol (PVA) nanofibers with a diameter of 490±83 nm were prepared using electrospinning techniques. And we select methyl blue, a common dye in the print and textile industry, as a model dye to investigate the water-stable nanofibrous membranes for environmental remediation applications. Based on the PEI/PVA nanofibers as a nanoreactor, we also fabricated the gold nanoparticle (AuNP)-containing nanofibrous membranes using in-situ reduction method for catalysis applications. The main content of this thesis include four parts:In the first section, we fabricated PEI/PVA nanofibers by electrospinning PEI and PVA mixture solution. The influence of the processing parameters such as flow rate, collection distance, voltage, and the polymer concentration on the morphology of the nanofibers was systematically investigated. In addition, different crosslinking methods including glutaradehyde solution, heat treatment and glutaradehyde vapor were employed to render the PEI/PVA nanofibrous membranes water stable. The formed PEI/PVA nanofibers with a smooth and uniform morphology before and after crosslinking were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and mechanical property testing. In the second section, the water stable PEI/PVA nanofibrous membrane was used for environmental remediation applications. We select methyl blue as a model contaminant to investigate the decoloration efficiency of the water stable PEI/PVA nanofibrous membranes, and preliminarily investigate the driving forces of the nanofibrous membranes to methyl blue. And the adsorption kinetics models and isotherms equations were established.The third section describes the fabrication of AuNP-incorporated composite nanofibrous membranes. The AuNPs with a diameter of 11.8±3.3 nm were synthesized and immobilized into the electrospun PEI/PVA nanofibrous membranes through in-situ reduction of the AuCl4- ions complexed with the water-stable PEI/PVA nanofibrous membranes. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and thermal gravimetric analysis (TGA) were utilized to characterize the morphology and composition of the AuNP-containing nanofibers.In the fourth section, AuNP-containing nanofibrous membranes were used for catalysis applications. We investigated the catalysis activity of AuNP-containing nanofibrous membranes and cast films under the same conditions, the catalytic activity of the formed AuNP-containing hybrid nanofibrous mats was evaluated via the transformation of 4-nitrophenol to 4-aminophenol. It is demonstrated that the catalysis activity of AuNP-containing nanofibrous membranes is higher than the cast film. And the formed AuNP-immobilized PEI/PVA nanofibrous membranes can be easily handled and reused for at least 3 times with similar catalytic performance. In addition, we also investigate the effect of temperature on the catalytic activity of the AuNP containing composite nanofibrous membranes. Results show that the morphology and catalytic performance of the AuNP containing composite nanofibrous membranes did not change, the AuNP do not show aggregation after heat treatment at different temperatures. The AuNP-containing composite nanofibrous membranes have satisfactory thermal stability at different temperatures (80℃-150℃)...
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