基于衬底/石墨烯/三元层状氢氧化物一体化电极的柔性微型超级电容器研究

Along with the rapid development of flexible electronic technology, the demand for high-performance energy storage devices are becoming more and more urgent. Among them, the flexible microsupercapacitors that can be directly integrated with flexible devices have attracted more and more attention. However, due to the performance limits of low capacity and durability, none of the current system can satisfy the practical requirements. Hence, this project plans to study on the controlled preparation of novel ternary Ni-based layered double hydroxides (LDHs) nanosheet array in-situ growth on the surface of duplicating/transferring prepared graphene coating flexible microstructural substrate by coprecipitated strategy at low temperature, which used to construct flexible microstructural substrate-graphene-LDHs array integrated electrode for high-performance flexible microsupercapacitors. Through researching the relation between microscale characteristics and preparation technology in detail, the growth mechanisms of ternary LDHs array will be addressed clearly. Moreover, the influences of morphology and structure, material composition and interface properties of integrated architecture on the supercapacitor performance will be investigated carefully to clarify the synergistic effect of energy storage between various compositions of the electrode. Furtherly, the ion/electron transfer principles of the integrated electrode under different stress and strain will be detailedly studied to elucidate the dependence between electrode kinetics and the material structure. Finally, the high-performance flexible microsupercapacitors with high energy density and cycling stability will be obtained, and the investigation of this project obtained results are expected to lay theoretical foundation and experimental evidence for the development of high-powered flexible energy devices in the future.

随着柔性电子技术快速发展，对高性能储能器件的需求日益迫切，其中能与柔性器件直接融合集成的柔性微型超级电容器逐渐兴起，但其现行体系却因受制于能量密度低、稳定性差等缺点，限制着其实际应用。本项目拟通过复形/转移构筑石墨烯覆层连续微结构柔性衬底复合体系，并在其表面采用低温共沉淀实现新型三元Ni基LDHs电极材料纳米片阵列原位生长，构建柔性微型超级电容器用具有柔性微结构衬底-石墨烯-LDHs阵列整体结构的新型柔性一体化电极。系统研究电极材料微结构特征与合成工艺参数关系，揭示三元LDHs阵列生长机制；分析一体化体系形貌结构、物质组成及界面性质对电化学性能影响规律，阐明电极组成相对超电容的协同作用机理；研究应力应变对电极离子传输/迁移率作用规律，建立一体化电极反应动力学和材料结构等方面关系，获得具有高能量密度及稳定性的柔性微型超级电容器，本项目完成将为柔性储能器件的发展提供有价值的理论基础和实验依据。

随着柔性电子技术快速发展，对高性能储能器件的需求日益迫切，其中能与柔性器件直接融合集成的柔性微型超级电容器逐渐兴起，但其现行体系却因受制于能量密度低、稳定性差等缺点，限制着其实际应用。本项目通过在Ni基LDHs电极材料低温共沉淀自组装法合成、衬底表面原位生长Ni基LDHs纳米片阵列合成及性能机制、Ni基LDHs电极材料形貌及结构与电化学性能关系及衬底/石墨烯/三元LDHs一体化柔性微超电容器构建等方面展开系统研究，完成Ni基LDHs电极材料低温共沉淀自组装及原位自组装生长纳米片最优制备工艺探索、不同Ni基金属/形貌与结构对LDHs材料比电容值影响机制分析、图案化柔性衬底-石墨烯复合体系制备探索、衬底-石墨烯-三元Ni基LDHs纳米片阵列制备工艺分析、一体化电极柔性微型超级电容器性能测试等方面研究内容，在Ni基LDHs制备及其原理、材料结构及组分与电化学性能之间关系、一体化电极柔性微超电容器设计、组装与性能表征方面取得一定进展。结果表明，共沉淀制备Ni/Co LDHs微球材料比电容值最高达2228 F/g（1 A/g）；由表面原位生长制备氮掺杂3D rGO-Ni/Mn LDHs组装柔性电容器最高比容量达420 F/g（1 A/g），最优能量密度134.83 Wh/kg、功率密度1.01 kW/kg；基于衬底/石墨烯/Fe-Ni/Mn LDHs一体化电极的柔性微超电容器比电容值最高达230 F/g（0.1 A/g），最优能量密度135.22 Wh/kg、功率密度0.16 kW/kg，循环1500次保持超过60%初始电容（20 mV/s），具有优异的电化学性能。本项目的完成对于发展高性能Ni基LDHs电极材料提供新思路，同时将为柔性储能器件的发展提供有价值的理论基础和实验依据。