基于自组装修饰银纳米线透明电极的柔性有机太阳能电池

Flexible Organic Solar Cells Based on Self-assembly Modified Silver Nanowires Transparent Electrode

银纳米线(AgNWs)透明电极具有出色的挠曲性和高电导率,是一类非常有潜力的柔性透明电极材料.然而AgNWs透明电极还存在表面粗糙度大、与衬底的附着力差、表面功函数与活性层能级不匹配等问题.针对上述问题,采用刮涂方法将AgNWs嵌入聚酰亚胺薄膜中,获得表面平整的AgNWs柔性透明电极,并通过Ag与巯基基团相互作用将五氟苯硫酚自组装到AgNWs电极表面,使AgNWs电极表面功函数从未处理的−4.88 eV提高到−5.06 eV,从而使其与活性层能级更加匹配.利用该电极作为柔性透明电极,在不采用任何阳极界面层的情况下制备的柔性有机太阳能电池最佳能量转换效率达到11.77%.本工作为AgNWs柔性电极的制备及功函数调控提供了新的研究思路,并为发展基于AgNWs柔性电极的高效柔性有机太阳能电池提供了一种简单有效的解决方案.

Silver nanowires(AgNWs)are a kind of flexible transparent electrode material with superior flexibility and high conductivity.However,AgNWs-based transparent electrode films always suffer some problems,such as large surface roughness,poor adhesion to the substrate,and mismatching between its work function and energy level of the active layer.In this work,the embedded AgNWs in polyimide(PI)substrate was prepared by bladecoating method,which demonstrates the AgNWs transparent electrode with smooth surface.Pentafluorothiophenol(PFTP)was self-assembled on the surface of AgNWs through interaction between Ag and sulfhydryl group,so that the work function of AgNWs electrode is increased from−4.88 eV to−5.06 eV,rendering it more matched with the energy level of the active layer.Based on the PFTP-modified AgNWs/PI substrate,the flexible organic solar cell without hole transport layer was fabricated by blade coating,and a power conversion efficiency of 11.77%was obtained.This work provides a novel idea for the preparation and work function regulation of AgNWs-based flexible electrode/substrate,and suggests a simple and effective method for the development of efficient flexible organic solar cells based on AgNWs flexible electrode.