Department of Materials Science and Engineering, National Cheng Kung University, Tainan 701, Taiwan.
ACS Appl Mater Interfaces. 2015 May 13;7(18):9479-85. doi: 10.1021/acsami.5b00428. Epub 2015 Apr 29.
Silver networks with high transmittance and low resistance were prepared on transparent substrates via a polymer-assisted electrospinning technique and post treatments. Nonaqueous media containing poly(methyl methacrylate) (PMMA) and silver trifluoroacetate (STA) were formulated and electrospun as polymer/metal-precursor nanofibers with as-spun fiber diameters ranging from 640 to 3000 nm. Nanofibers randomly deposited on transparent substrates formed a plane scaffold, which served as the raw material for the conducting silver network. Post-thermal treatment at a moderate temperature of 100 °C reduced the STA precursors to silver nanoparticles (Ag NPs). Further heat treatment at elevated temperatures thermally decomposed the organic polymer and triggered sintering of the Ag NPs into a connected one-dimensional (1D) domain. Silver fibers with diameters ranging between 800 and 4500 nm formed continuous conducting networks on the substrate surface. The sheet resistances of these conducting silver networks revealed strong correlations with the original STA/PMMA ratios and with the silver network morphologies after the polymers were removed. The material fabrication was carefully investigated, and the surface plasmon resonances (SPRs), fiber morphologies, and electrical and optical properties of the products were examined. The optimized conducting silver networks exhibited sheet resistances as low as 15 Ω/sq and diffusive optical transparencies of approximately 54%.
通过聚合物辅助静电纺丝技术和后处理,在透明基底上制备了具有高透过率和低电阻的银纳米网络。配制了含有聚甲基丙烯酸甲酯(PMMA)和三氟乙酸银(STA)的非水介质,并将其纺成具有 640 至 3000nm 不等的初生纤维直径的聚合物/金属前体纳米纤维。随机沉积在透明基底上的纳米纤维形成了一个平面支架,作为导电银网络的原始材料。在 100°C 的中等温度下进行后热处理,将 STA 前体还原为银纳米颗粒(Ag NPs)。进一步在较高温度下进行热解,有机聚合物分解,并引发 Ag NPs 烧结成一维(1D)连通域。直径在 800 至 4500nm 之间的银纤维在基底表面形成连续的导电网络。这些导电银网络的面电阻与原始 STA/PMMA 比以及聚合物去除后银网络形态之间存在很强的相关性。对材料的制备进行了仔细的研究,并对产物的表面等离子体共振(SPR)、纤维形态以及电和光性能进行了研究。优化后的导电银网络表现出低至 15Ω/sq 的面电阻和约 54%的扩散光透明度。