基于层层组装技术的自修复电致变色膜的研究

The compelling needs of next-generation electronics would require stretchable, foldable and even wearable electronic devices, including flexible electrochromic devices. However, the reliability and lifespan of flexible electrochromic devices can be seriously decreased by the internal micro-cracks or partial injuries during the process of frequent stretching, folding, and screwing in practical applications. Motived by this need, we propose to introduce the self-healing into the electrochromic devices for realization of its self-healing to enhance operation lifespan. In this research, the multilayer films of inorganic electrochromic materials and polymers will be constructed based on the hydrogen-bonding or electrostatic interactions by layer-by-layer assembly technique. By changing the nano-structures and compositions of inorganic electrochromic materials, the molecular weight of polymers, and the construction conditions, the research on assembly process, film structure, electrochromisim, and self-healability of the assembled multilayers will be carried out. Furthermore, we will check the self-healable electrochromic film based on the coordination-bond. The effects of the driving force on the electrochromic property and the self-healing property of the assembled multilayers will be discussed. The development of this project will provide a feasible method to build up the self-healable, flexible electrochromic decives.

新一代电子器件的发展，迫切需要可伸缩的、可折叠的，甚至可穿戴的柔性电子器件，其中包括柔性电致变色器件。但柔性电致变色器件在实际使用过程中，由于反复伸缩、折叠、扭曲，不可避免地产生内部的微观裂纹和局部损伤而导致器件可信度和使用寿命的下降。本项目将自修复概念引入到电致变色领域，制备具有自修复功能的电致变色膜，赋予电致变色器件自修复功能。拟将无机电致变色材料和聚合物基于氢键或静电作用，通过层层组装技术构筑成膜; 通过改变无机电致变色材料的纳米组成结构、聚合物的分子量及组装条件，研究多层膜的组装过程、膜结构、电致变色性能和自修复性能; 并进一步发展基于配位键的自修复电致变色膜，研究成膜驱动力对多层膜体系的电致变色性能和自修复性能的协同影响机制。本项目的开展为制备具有自修复功能的柔性电致变色器件提供研究思路和实验基础。

柔性电致变色器件在实际使用过程中，由于反复伸缩、折叠、扭曲，不可避免地产生内部的微观裂纹和局部损伤而导致器件可信度和使用寿命的下降。基于共价键和非共价键可逆性这一特点，自修复材料恰恰能够修复这样的裂纹和损伤。本项目旨在制备出具有自修复功能的电致变色材料和聚合物的无机/有机复合膜。首先，我们成功合成出了无机电致变色材料—具有纳米结构的氧化钒和过氧化聚多钨酸（PTA），PTA可进一步用于制备氧化钨（WO3）材料。其次，使用不同制备方法，制备出WO3和聚合物的无机/有机复合膜材料。采用层层组装方法，基于氢键作用构筑了具有自修复性能的（聚丙烯酸/聚氧化乙烯&WO3）复合膜；通过电化学沉积方法，成功制备出具有优异循环特性的电致变色（WO3&聚多巴胺）复合膜。另外，我们成功合成出聚乙烯亚胺-g-聚乙二醇接枝共聚物，将在后续的研究中用作构筑基元制备自修复聚合物多层膜。