导通取向的有序纳米阵列膜及其全柔性超级电容储能研究

In this research project, flow-through oriented flexible nanoarray conductive polymer composite membranes have been designed to act as supercapacitor electrode material for electrochemical energy storage. Titania nanotube array with independent tube wall structure has been synthesized by a selective anodization process, which is directly supported on flexible titanium microgrid array. Titanium nitride (TiN) nanotube array is then formed by an ammonium reduction process of as-prepared titania (TiO2). The conductive polymers of polypyrrole (PPY) and poly 3, 4-ethylenedioxythiophene (PEDOT) are respectively coated on TiN inter-tube wall and inner-tube wall using a pulse voltammetry electro-polymerization method to form flexible nanoarray membrane of PPY-TiN-PEDOT. Flow-through oriented nanoarray conductive polymer membranes are accordingly synthesized by the modulated chemical corrosion process. PPY-TiN-PEDOT with a single nanochannel structure is formed by selectively removing the barrier layer of TiN nanotubes. PPY-PEDOT with a dual nanochannel structure is formed by completely removing TiN nanotubes. Finally, fully flexible all-solid-state supercapacitor has been constructed using symmetric pair electrodes of PPY-TiN-PEDOT, a common electrode of PPY-PEDOT and polyvinyl alcohol gel electrolyte. The reversible ion doping/undoping reaction process of P-type PPY and N-type PEDOT contributes a high Faradic pseudo-capacitance performance, which accordingly results in an effective energy storage.

本项目设计合成导通取向的钛基有序纳米阵列导电聚合物复合膜，构建高容量储电的全柔性超级电容器。首先，采用选择性阳极氧化方法合成柔性钛微米网格支撑的、管壁分离结构的二氧化钛TiO2有序纳米管阵列，氨气氮化方法合成高电导性氮化钛TiN有序纳米管阵列；其次，通过提高钛基底与纳米管界面TiO2阻挡层电导性，采用脉冲伏安电聚合方法在TiN有序纳米管骨架的管间隙和管内部依次原位合成高柔韧性和高掺杂率导电聚吡咯PPY和聚3，4-乙撑二氧噻吩PEDOT；然后，通过局域化学腐蚀溶解纳米管阻挡层封闭端或者纳米管骨架，分别形成单通道导通取向PPY-TiN-PEDOT以及双通道导通取向PPY-PEDOT有序纳米管阵列柔性复合膜。最后，基于柔性有序纳米阵列和多通道特征的PPY-TiN-PEDOT电极对和PPY-PEDOT共电极构建全柔性超级电容器，通过匹配离子P型和N型掺杂/去掺杂法拉第过程实现高容量储电性能。

全柔性电子器件必然要求匹配外形轻薄、可折叠卷曲供应电源，高容量全柔性超级电容器是理想的储能器件。微结构调控的柔性电极材料对于构建柔性储能器件至关重要。本项目分别设计合成了导通取向的自支撑导电聚合物有序纳米膜电极材料以及柔性基底负载电活性导电聚合物有序纳米膜电极材料，并应用于高容量储电性能的全柔性全固态超级电容器。以二氧化钛纳米管阵列为模板，合成导通取向的自支撑结构聚吡咯、聚苯胺、聚乙撑二氧噻吩单组分有序纳米管或纳米孔阵列以及聚吡咯-聚苯胺双组分有序纳米孔阵列柔性膜电极材料，并应用于全柔性超级电容器实现电化学储能。自支撑导电聚合物纳米阵列膜电极材料表现出较好的机械柔韧性和较一般的电化学稳定性。以柔性钛箔为基底，以氮化钛纳米管阵列为骨架负载聚吡咯和聚苯胺纳米复合膜，合成一体化结构的钛箔基聚吡咯/氮化钛、聚苯胺/氮化钛和聚吡咯/氮化钛/聚苯胺纳米孔阵列柔性膜电极材料，通过高电导性氮化钛提高导电聚合物的倍率特性和高比电容性能。以柔性碳纤维为基底，合成一体化结构的碳纤维基聚吡咯/氮化钛和聚苯胺/氮化钛纳米线阵列柔性膜电极材料，提高导电聚合物的柔韧性和微结构稳定性。钛箔基或碳纤维基氮化钛骨架支撑的导电聚合物纳米阵列柔性膜电极材料表现出比自支撑导电聚合物纳米阵列柔性膜电极材料更高的比电容性能和电化学循环稳定性。在此基础上，采用电导性碳量子点或氧化还原活性磷钼酸修饰聚苯胺，合成电导性改性修饰的碳纤维基碳量子点/聚苯胺和电活性改性修饰的磷钼酸/聚苯胺有序纳米线阵列柔性膜电极材料，碳量子点/聚苯胺表现出高倍率性能和循环稳定性，磷钼酸/聚苯胺表现出高比电容特性，进一步提升柔性导电聚合物的电化学储电性能。基于导通取向和自支撑的导电聚合物或者钛基(或碳纤维基)柔性基底负载导电聚合物以及匹配凝胶聚合物电解质，构建全柔性全固态超级电容器，实现高循环稳定性能和高电容性能的电化学储能器件。