可控结构的图形化银纳米线柔性透明导电薄膜研究

With the development of electronic devices to the miniaturization and portability, the flexible transparent conductive films are attracting more and more people’s attention. The major problem currently facing is how to obtain the graphical flexible transparent conductive film with high quality and controllable structure by the design of the materials system and the preparation technology. In this project, the inkjet printing electronic technology will be introduced to fabricate the graphical silver nanowires-based flexible transparent conductive films with controllable structure. Based on the in-depth study of the preparation method of silver nanowires which could be applicable to the inkjet-printing electronic technology and the preparation of ink and the heat treatment before and after inkjet-printing, the mechanism of preparation of silver nanowires with controllable size by ultrasonic induced fracture technology and the relationship among the rheological properties of ink and the morphology of silver nanowires and the performance of ink and the microstructure of the film. We will put forward the principle of the composition design and the preparation method and the relationships among the inkjet printing electronic technology and the performance of ink and the technological parameter and the heat treatment and the microstructure and optoelectronic properties of film and reveal the mechanism of the electronic transmission in the microstructure of film and the interaction between the light and microstructure of film. The studies of the theoretical analysis and the materials design and the preparation technology will provide the theoretical and experimental basis for the graphical flexible transparent conductive film prepared by inkjet printing electronic technology.

随着电子产品不断向小型化和便携式等方向发展，柔性透明导电薄膜将作为未来发展趋势正引起人们越来越多的关注。目前科学家所面临的一个最大的挑战就是如何通过材料体系的设计和制备技术的调控在柔性衬底上制作高质量、高可控性和可重复性的可图形化的柔性透明导电薄膜，使其在光电性能和高效低成本等方面达到所需的水平。本课题拟开展喷墨印制电子技术制备可控结构的图形化银纳米线柔性透明导电薄膜的研究。通过深入研究超声诱导断裂银纳米线机理、墨水配制、喷印工艺和热处理技术等方面，提出喷墨印制银纳米线墨水的组分设计原则和制备方法，揭示银纳米线墨水流变学特性、墨水性能-喷印工艺参数-热处理技术-薄膜微结构-光电性能间关系以及薄膜微结构间电子传输机制和光波与表面微结构间的相互作用关系等。本课题将从机理分析、材料设计和制备方法研究三个方面为采用喷印技术制备可控结构的可图形化柔性透明导电薄膜提供理论支持和实验依据。

随着电子产品不断向小型化和便携式等方向发展，柔性透明导电薄膜将作为未来发展趋势正引起人们越来越多的关注。目前科学家所面临的一个最大的挑战就是如何通过材料体系的设计和制备技术的调控在柔性衬底上制作高质量、高可控性和可重复性的可图形化的柔性透明导电薄膜，使其在光电性能和高效低成本等方面达到所需的水平。本项目主要研究内容是采用喷墨印制工艺制备可控结构的图形化纳米银线柔性透明导电膜。通过深入研究溶剂热法制备可控结构纳米银线以及超声诱导断裂银纳米线的工艺和机理获得长2～5 μm，直径20-30 nm的纳米银线，适用于喷墨印制工艺。通过理论与实验研究相结合，深入探讨了溶剂、功能助剂、纳米银线的形貌和浓度等对纳米银线墨水的物化特性、喷印工艺、纳米银线导电图案的结构和精度等影响，提出喷墨印制银纳米线墨水的组分设计准则和制备方法。最终选择体积比3：2的乙二醇和异丙醇为混合溶剂，改性聚硅醚类助剂为润湿剂，配制纳米银线墨水，通过调控润湿剂含量可获得粘度7～8 mP∙s，表面张力为23～24 N/m，墨水与PET基底表面接触角24～25º的纳米银线墨水。所配制的纳米银线墨水不仅具有良好的稳定性和喷印适应性，而且不需要对PET表面进行特殊处理。 通过对纳米银线浓度、喷墨印制工艺（包括墨滴间距、打印频率、喷嘴个数、基底温度、喷嘴温度等）和热处理工艺等对喷印纳米银线柔性透明导电图案的光学、电学、雾度、微观结构等影响研究，揭示银纳米线墨水性能-喷印工艺参数-热处理技术-薄膜微结构-光电性能关系，提出喷墨印制技术制备AgNWs-FTCF的工艺调控准则。配制0.38 mg∙mL-1的纳米银线墨水，采用16孔进行打印，打印频率7500 Hz，PET基底温度40℃，喷嘴温度35℃，喷印样品在60℃后热处理10 min，可获得光透射率 83.1% （550 nm），方阻 34 Ω∙sq-1的透明导电薄膜。