Preparation And Properties Of Electrospun Fibers Supported On Noble Metal Nanoparticles

Electrospinning is an effective method for the preparation of nanofibers which had the features of simple preparation,extensive raw material,controllable fiber morphology and continuous preparation.In order to expand the application,electrospun fibers were associated with other functional materials.As one of the functional material,noble nanoparticles have many unique physical and chemical properties,which made the noble metal nanoparticles composite electrospun fibers suitable for a wide range of applications in the SERS,catalysis,sensing and other fields.How to prepare the electrospun composite fiber by a simple and effective method is the main problem.The polyacrylic acid(PAA)/ polyvinyl alcohol(PVA)was used as the matrix material,and the nanoparticles deposited electrospun fibers were prepared by simple immersion and blending during which the interaction between the noble metal nanoparticles and the fibers was introduced.The main research contents and results are as follows:(1)The positively-charged Au NPs were utilized as building blocks for the preparation of SERS substrates.Driven by electrostatic interaction,the Au NPs were attracted on the crosslinked poly(acrylic acid)(PAA)/poly(vinyl alcohol)(PVA)electrospun nanofibers through simple immersing.The composite fibers had excellent SERS enhancement and SERS signal uniformity.And the SERS enhancement in the depth direction was also proved to be excellent through testing the SERS performance at different depth points on the substrate,which showed that the electrospun fiber membrane loaded with gold nanoparticles is an excellent 3D SERS substrate.(2)The anisotropic gold nanorods were supported on the surface of electrospun PAA / PVA fibers by a similar simple soaking method,and the effects of spinning time,immersing time and the concentration of gold nanorod on the SERS performance of the composite fiber were investigated.The results showed that the SERS enhancement of the composite fiber improved with the increase of the spinning time and the concentration of the gold nanorod and the SERS performance of the composite fibers improved first and then reached equilibrium at 12 h.The composite fibers exhibited excellent SERS enhancement and uniformity,and the SERS substrate could exhibite excellent SERS enhancement after 45 days(3)Another kind of anisotropic nanoparticle-palladium nanocube(PdNCs)were loaded on the surface of electrospun PAA / PVA fiber by a similar method.The catalytic performance of the obtained composite fibers was examined by the reaction of 4-nitrophenol catalytic reduction.The results showed that the PdNCs loaded PAA / PVA electrospun fibers had excellent catalytic activity and reproducibility.And the composite nanofiber could quickly catalyze the reduction of 4-nitrophenol.4-nitrophenol conversion rate could reach more than 97% in 6 times the repeated catalysis.(4)The electrospun PAA / PVA composite fibers with nanoparticles loaded both inside and outside were prepared by blending first and then immersing.Gold nanoparticles were dispersed inside of the PAA / PVA electrospun fibers by blending.Driven by the electrostatic interaction,the noble metal nanoparticles with different morphologies were then loaded on the surface of the fiber.The SERS and catalytic properties of the composite fibers were tested.And the result showed that the SERS performance and catalytic performance of composite fiber with high nanoparticle capacity are more excellent than the fibers with low nanoparticle capacity.