基于关联金属/金属纳米线复合结构的柔性透明导电薄膜的构筑及性能研究

As the fast development of optoelectronics industry in the fields of energy, information, defense, the improved performance of the transparent conductive film, such as higher transmittance and lower sheet resistance even the flexibility are required now. While the traditional transparent conductive materials is gradually constrained due to the limitation in resources supply or the bottleneck of performance, and therefore an alternative is needed urgently. This project aims to break the bottleneck in the material and micro-architectural design, which are considered as two approaches to achieve transparency and conductivity simultaneously. The materials we intended to study are correlated metals and metal nanowires, which can be prepared on flexible/rigid substrates by widely used industrial production technologies. Combing with material simulation, we intend to reveal how the electron correlation characteristic, band structure, optical function and morphology affect the optoelectronic performance of the correlated metals film and metal nanowires network, and find out an optimized ways for both materials. On this basis, we plan to integrate these two materials film together as a composition structure, fully using their strong points to offset their weaknesses, and investigate the effects of composite composition and composite form to the film properties. Finally, we would comprehensively evaluate the performance according to their application in various optoelectronic devices. This study attempts to answer the following two key scientific questions: 1. What’s the link between the structure and properties in the correlated metal and material based transparent and conductive thin films; 2. The mechanism of how the composite form affect the transparent conductive properties. The implementation of this project is supposed to provide key materials and technologies for the optoelectronic industry and has important scientific significance and application value.

面向能源、信息、国防领域的光电产业的不断扩张升级对透明导电薄膜的透过率、方阻以及柔性化提出了更高的要求。而传统材料从性能与资源方面都逐渐受到掣肘，因此亟需寻求替代品。本项目以材料调控与微结构设计这两种透明导电实现方式中存在的瓶颈为突破点，拟将关联金属和金属纳米线作为研究载体，利用可规模化加工技术在柔/刚性衬底上制备薄膜，结合电子关联特性、能带结构、光学函数、形貌等方面的材料模拟探索薄膜性能变化规律与优选依据。在此基础上，合理实现这两种材料在结构与性能上的优势互补，探索不同复合形式对性能的影响机制，并综合评价其在柔性光电子器件上的性能表现及工业应用可行性。在研究中试图回答以下两个关键性科学问题：1. 关联金属以及金属纳米线中材料结构与薄膜性能间的构效关系；2. 复合形式对透明导电性能的影响机制。本项目的成功实施能对光电产业领域的发展提供关键材料与技术，具有重要的科学意义与应用。

本项目以利用透明导电薄膜的优化设计实现能源利用效率提升为核心，重点探索了银纳米线与氧化物薄膜材料及其透明导电薄膜的制备方法，深入理解了高透过率与高电导率的透明导电窗口的实现原理，探索出了一条可用于柔性光电器件的透明导电薄膜工艺路线，掌握了材料制备及器件设计中的若干关键技术。项目在研发过程中密切联系工业界，探索并深入了解了产业应用的可行性与亟待突破的瓶颈。. 项目围绕这些需求开展了材料性能的提升，通过电子束辐照将金属纳米线稳定性提升数倍；利用水蒸发过程中的巨大毛细作用力实现焊接金属纳米线，用温和的方式突破电子传输瓶颈。在面向柔性与穿戴式应用中，项目发展了冷冻转移原理，实现了利用超薄弹性体实现可拉伸的透明导体；与医学领域合作开发了可呼吸的复合透明导电薄膜，可作为高性能的表皮电子器件监测生理信号；利用透明导电材料的高透过优势，组合电和光两种响应模式量化和映射压力，设计了接近真实人类皮肤感知能力的电子皮肤，可应用于机器人与假肢等领域。项目在光电器件中取代传统透明导电材料ITO过程中，实现了报道时最高的柔性红光量子点发光二极管外量子效率；利用高雾度的透明导电电极显著提升了半透明钙钛矿光伏电池的效率，为全印刷光电器件的应用提供了电极的解决方案。项目还积极拓展透明窗口与红外调控能力的结合实现能效提升，将辐射制冷的原理引入项目研究，利用对阳光透明的辐射体与传统节能功能层结合可以降低窗户温度，优势互补提升节能效果，可以将典型建筑的年制冷节约能耗为20-49 MJ m-2，展示了巨大的应用价值。项目成果在国际主流 SCI高水平刊物上发表学术论文8篇，受到学术领域与媒体的关注，建立了良好的国际国内合作关系。基于本项目的研发基础，项目负责人作为骨干参与了国家重点研发计划关于透明节能窗薄膜开发，为未来推动透明导电材料在能效提升领域的应用奠定了基础。