铜铁氧化物核壳中空管阵列的构筑及赝电容负极性能研究

Based on the current research problem of pseudocapacitors that the capacity of their cathode materials is much lower than that of the existed anode materials, this project aims to design and construct the CuO@Fe3O4 core-shell tubular nanoarray materials with sheet-like Fe3O4 coated on the hollow CuO surface, in order to obtain a kind of pseudocapacitive cathode materials with high specific capacity that can match with the existing anode materials. Using the prepared CuO@Fe3O4/Cu materials, we will investigate the relationship between their especial chemical composition and hierarchical micro nano-array structure and their electrochemical behavior as cathode, study the mechanism of charge-discharge. At the same time, we will investigate the valence changes and synergy mechanism of copper and iron elements during the electrochemical oxidation-reduction process. These studies will provide theoretical and experimental basis for the construction of high performance pseudocapacitive cathode materials. Further, the CuO@Fe3O4/Cu will be used as cathodes and the early researched Cu(OH)2@NiCo composite hydroxide/Cu as anodes for assembly of novel asymmetric cell type pseudocapacitors. The performances of the pseudocapacitors, including energy density, power density, efficiency, cycle stability and temperature tolerance will be investigated. With these work, we want to obtain high-performance pseudocapacitors that have both the advantages of capacitor and the high energy density of lithium-ion batteries. The purpose of this project is to solve the practical application problems in energy storage and charge-discharge due to low energy density of supercapacitors and low power density of lithium ion batteries.

针对当前赝电容器负极材料比容量远低于正极材料难题，本项目拟设计和构筑片状Fe3O4包覆在CuO中空管表面的CuO@Fe3O4 核壳阵列材料，以获得具有能与已研究出来的赝电容正极材料比容量相匹配的负极材料。我们将考察所获得的CuO@Fe3O4/Cu材料的特殊的化学组成和多级微纳阵列结构与电化学行为的内在联系及其充放电机理，研究铜和铁两种元素在电化学氧化-还原过程中的价态变化和协同作用机理，为高性能赝电容负极材料的构筑提供理论和实验基础。进一步以该材料为负极、前期研究出来的Cu(OH)2@NiCo复合氢氧化物/Cu等相关材料为正极，组装新型不对称电池型赝电容器，考察其能量密度、功率密度、倍率、循环稳定性和温度耐受性等电容器性能，使之在具有电容器本身优点的同时，具有能与锂离子电池相匹敌的能量密度。本项目意图解决由于超级电容器能量密度低、锂离子电池功率密度低而导致的储能及充放电等实际应用问题。

针对当前赝电容器负极材料比容量远低于正极材料难题，本项目设计和构筑了片状Fe3O4包覆在CuO中空管表面的CuO@Fe3O4 核壳阵列、NiOOH修饰的 α-FeOOH 纳米片阵列、Ta掺杂Cu7S4、卤素阴离子修饰的 β-FeOOH、Fe7S8修饰α-FeOOH和以类普鲁士蓝化合物为前体合成的多孔CuS棱柱材料，获得了能与已研究出来的赝电容正极材料比容量相匹配的负极材料（比容量在1 A g−1电流密度下高于1850 F g−1）。考察所获得的以上负极材料的特殊的化学组成和多级微纳阵列结构与电化学行为的内在联系及其充放电机理，研究了铜和铁两种元素在电化学氧化-还原过程中的价态变化和协同作用机理，为高性能赝电容负极材料的构筑提供了理论和实验基础。进一步以该材料为负极、以前期研究出来的Cu(OH)2@NiCo复合氢氧化物/Cu等相关材料为正极，组装了新型不对称电池型赝电容器，考察了它们的能量密度、功率密度、倍率、循环稳定性和温度耐受性等电容器性能，结果表明，这些组装的器件具有电容器本身优点的同时，还具有能与锂离子电池相匹敌的能量密度。本项目解决了由于超级电容器能量密度低、锂离子电池功率密度低而导致的储能及充放电等实际应用问题。