靜電紡絲技術(shù)

J.Am.Chem.Soc.2014,136,16716?16719整理課件靜電紡絲技術(shù)將前驅(qū)體溶液帶上高壓靜電，帶電的聚合物液滴在電場(chǎng)的作用力下于毛細(xì)管的Taylor錐頂點(diǎn)被加速。當(dāng)電場(chǎng)力足夠大時(shí)，聚合物液滴可克服表面張力形成噴射細(xì)流。細(xì)流在噴射過(guò)程中溶劑揮發(fā)或固化，最終落在接受裝置上，形成類(lèi)似非織造布狀的纖維氈。整理課件納米纖維定義：美國(guó)國(guó)家科學(xué)基金會(huì)(NSF)定義納米纖維為至少在一維空間尺度上小于100nm的纖維。無(wú)紡布工業(yè)一般認(rèn)為直徑小于1μm的纖維就是納米纖維。

特點(diǎn)：在微觀上表現(xiàn)為納米結(jié)構(gòu)，具有納米材料具有的一切特性；而在宏觀上表現(xiàn)為網(wǎng)氈結(jié)構(gòu)，可以在重力作用下自然沉降而分離。整理課件ACSAppl.Mater.Interfaces2011,3,369–377Nanolett2004,4,933Nanolett2004,4,933整理課件實(shí)驗(yàn)部分：紡絲液：PVP(K-30)、TBOT(鈦酸丁酯，鈦源)、DIPA(偶氮二羧酸二異丙酯，發(fā)泡劑)；無(wú)水乙醇、醋酸作溶劑。靜紡TiO2nanofibersPVP/TBOT/DIPAfibers煅燒DIPA,分子式為C8H14N2O4，在160℃左右完全分解為氣相CO2、NO2、H2O。整理課件Fig.1(a-b)TypicalSEMimagesoftheas-spunpolymerprecursorofSampleA1underdifferentmagnifications.(c-e)TheelementmappingsofTi,OandNwithinasingleprecursorfiberunderSEM.整理課件Fig.2(a,b)SEMimagesoftheTiO2mesoporousnanofibers.(c)TEMimageofasinglemesoporousTiO2nanofiber.(d)XRDpatternofSampleA1aftercalcination.(e)Nitrogenadsorption?desorptionisothermoftheTiO2mesoporousnanofibers.(f)Correspondingporesizedistribution.整理課件Fig.3(a-b)SEMimagesoftheelectrospunpolymerfibersofSampleA2.(c-d)SEMimagesofthecalcinedproductsofSampleA2.(e)XRDpatternrecordedfromthecalcinedproductsSampleA2.(f)Nitrogenadsorption-desorptionisothermofthecalcinedproductsofSampleA2.整理課件Table1.SurfacepropertiesoftheTiO2mesoporousnanofibersofSampleA1andA2aswellasP25整理課件Fig.4(a)Hydrogenproductionphotocatalyzedbytheas-fabricatedmesoporousTiO2nanofibers,solidTiO2nanofibers,andP25underdifferentirradiationtime.(b)ResultsofreusabilityexperimentsforphotocatalyticH2generationusingthepresentthreephotocatalysts.(c)Schematicillustrationofmesoporousfiberswithenhancedphotocatalyticactivities.整理課件Fig.5AverageH2evolutionratesoftheas-fabricatedmesoporousTiO2fibers,solidTiO2fibersandP25.整理課件Table2.ComparisonoftherelatedworkforphotocatalyticH2