叠层有序银纳米线网格电极的可控制备及其在有机太阳能电池中的应用

Ag nanowires (AgNWs) with their high conductivity, excellent flexibility and solution processing have proven to be the most promising candidate alternative to ITO and have been widely investigated and applied. For the spin-coated random AgNW films, nanowire aggregation and stacking occur, leading to large surface roughness and easily short circuit for organic photovoltaic devices. This project aims at introducing a water-bath assisted convective self-assembly of AgNWs at a temporary water/alcohol interface and then transfering these aligned AgNWs onto a desired substrate to form hierarchical aligned AgNW mesh electrodes for the organic photovoltaic devices by dip-coating orthogonally to the previous layer. The key research is focus on analyzing the effect of these factors on the self-assembled process, such as, water-bath temperature, size and capping agent of AgNWs, and properties of the AgNW dispersion, investigating physical mechanism of solvent flow induced AgNW self-assemble, to obtain a controllable solvent-flow induced metal nanowire self-assembly and manipulating the structure of AgNW mesh electrodes to improve their performance. We will discuss the adhesion of AgNW mesh electrodes to the substrates and their ambient durable. This project will be provided technique support for the performance improvement of AgNW transparent conductive electrodes and application for organic photovoltaic devices.

银纳米线(AgNWs)由于具有高的导电率、柔性和溶液加工等特点已成为最有希望替代ITO的透明导电电极材料而获得广泛研究和应用。针对旋涂等溶液加工方法制备的AgNWs薄膜存在堆积现象，导致其表面粗糙度高，在有机光伏器件应用中容易产生短路现象。本项目拟采用水浴辅助产生溶剂流诱导AgNWs在水/醇界面上的自组装，形成单层有序AgNWs薄膜，通过多次正交浸渍提拉形成叠层有序AgNWs网格电极，并研究其在有机光伏器件中的应用。将重点研究水浴温度、AgNWs的尺寸与表面配体及其分散剂的特性等因素对自组装过程的影响，澄清溶剂流诱导AgNWs自组装的物理机制，发展可控的溶剂流诱导金属纳米线自组装方法并调控AgNWs网格电极的结构来改善其性能，探讨AgNWs网格电极与衬底的粘附性及其环境稳定性。本项目将为AgNWs透明导电电极性能的提升及其在有机光伏器件中的应用提供技术支撑。

银纳米线(AgNWs)由于具有高的导电率、柔性和溶液加工等特点已成为最有希望替代ITO的透明导电电极材料而获得广泛研究和应用。针对旋涂等溶液加工方法制备的AgNWs薄膜存在堆积现象，导致其表面粗糙度高，在有机光伏器件应用中容易产生短路现象。本项目采用水浴辅助产生溶剂流诱导AgNWs在水/醇界面上的自组装，形成单层有序AgNWs薄膜，通过多次正交浸渍提拉形成叠层有序AgNWs网格电极，并研究其在有机光伏器件中的应用。研究了溶剂流诱导AgNWs自组装的物理机制，讨论了水浴温度、AgNWs尺寸和分散剂性质、提拉衬底粗糙度等因素对自组装过程的影响；发现在80℃的水浴温度下三次正交浸渍提拉形成叠层有序银纳米线网格电极的方阻为16.7 Ω/□，透射率为93.4%，表面粗糙度为13.2 nm，品质因子为327，基于P3HT:PC61BM为活性层聚合物太阳电池的光电转换效率为4.01%。研制倒装柔性银纳米线(PET/Flip-AgNWs)透明导电薄膜，其表面粗糙度为3.68 nm，1000次弯折后方块电阻几乎不变，倒置结构（PET/Flip-AgNWS/ZnO/P3HT:PC61BM/MoO3/Ag）聚合物太阳电池的光电转换效率为4.72%。采用多元醇还原法，合成了弯折AgNWs并研究了其形成过程的物理机制，探讨了弯折型和直线型AgNWs的等离子体共振效应和光散射作用对聚合物太阳电池器件性能的影响。此外，开发出了新型聚合物太阳电池的电极界面修饰材料和烷硫链修饰的有机太阳能电池给体材料，研制出新型给体聚合物材料与ITIC-F共混活性层的器件光电转换效率高达11.7%。