Electrospinning Construction And Performances Of Photoluminescence-Electricity-Magnetism Multifunctional Nanofiber Yarns

Recently,multi-functional nanomaterials have made up for the singleness of ultilization of mono-functional materials to achieve the multi-functionality of materials under the condition of a specific size,which have attracted the attention of scientific researchers.Nanofiber yarn is a kind of one-dimensional?1D?nanomaterials with regular structure,which is composed of highly oriented nanofibers.Electrospinning is one of the simple and efficient ways to obtain nanofiber yarns and multi-functional nanomaterials.Therefore,it is very meaningful to endow nanofiber yarns with multifunctionality by electrospinning technology in order to expand the range of practical application of nanofibers.In this dissertation,a conjugated electrospinning device was established.Further,nanofiber yarns with multifunctional properties assembled from nanofibers have been prepared by conjugate electrospinning method,including[Fe₃O₄/PAN]//[Eu?BA?₃phen/PAN]magnetic-fluorescent bifunctional nanofiber yarns,[Fe₃O₄/PANI/PAN]//[Eu?BA?₃phen/PAN]fluorescent-electrical-magnetictrifunctionalnanofiberyarns,{[Tb?BA?₃phen+Eu?BA?₃phen]/PAN}//[PANI/PAN]tunable fluorescent color-electricity bifunctional nanofiber yarns and{[Eu?BA?₃phen+Tb?BA?₃phen]/PAN}//[Fe₃O₄/PAN]tunable luminescent color-magnetism bifunctional nanofiber yarns.The prepared nanofiber yarns were systematically characterized using a series of modern techniques such as XRD and SEM.The results reveal that the obtained nanofiber yarns have large aspect ratios and uniform diameters,the nanofibers in the yarns demonstrate high orientation and are closely packed together.The novel nanofiber yarns are composed of two different types of nanofibers,so that the electrical and magnetic materials and the rare earth complexes are only existed in the respective nanofibers,and the direct contact between the light-absorbing substances?the electrical and magnetic materials?and the light-emitting substances?the rare earth complexes?is effectively avoided.Consequently,the overall fluorescence performance of the yarns is significantly enhanced,which overcomes the disadvantages of poor fluorescent performance of the conventional composite multifunctional nanomaterials.In addition,the fluorescent performance,electrical conductivity and magnetic property of nanofiber yarns can be modulated by changing the contents of rare earth complexes,polyaniline and Fe₃O₄ nanoparticles.The new nanofiber yarns have potential applications in the fields of nanodevices,fluorescent labels,electromagnetic shielding,gas sensors,etc.owing to their unique multifunctional properties.The design conception and preparation method presented in this thesis also provide a simple and effective way for constructing other dual-function or multi-functional nanofiber yarns.