多维度V2O5基半导体异质结纳米阵列增强超级电容器存储与传输性能的研究

作为一种能量存储与转换装置，超级电容器具有功率密度高、充电时间短、使用寿命长等优点受到学者们的广泛关注。过渡金属化合物半导体能够通过快速的法拉第氧化还原反应提供额外的赝电容，其理论比电容远大于碳材料。在导电集流体上直接制备半导体纳米阵列相比于传统涂覆电极可以避免使用粘接剂、减小界面电阻、增大比电容和能量密度。根据材料设计的思想，选择高比电容、容易生长、形貌可控的化合物半导体材料组合。首先在导电集流体上生长二维V2O5纳米带阵列，然后在二维V2O5纳米带阵列上复合另一种化合物半导体纳米阵列形成异质结。这种全新的异质结纳米阵列结构不仅具有两种半导体材料的储能优势，还能提高电子的迁移率。本项目探索一种低成本制备高比电容V2O5基化合物半导体异质结纳米阵列的方法，研究其作为超电容电极材料的协同作用与失效机制，为大幅度提高超电容比容量、能量和功率密度提供理论和实验依据。

As a new type of energy storage and conversion devices, supercapacitors have attracted great attention due to their advantages of high power densities, short charging time and long service life, etc. Transition metal compound semiconductor could provide extra pseudocapacitance through fast faradic redox reaction. And their theoretical specific capacitance values are greater than those of carbon materials. Compared with traditional coating electrodes, direct growth of semiconductor nano-arrays on current collector could avoid using adhesives, reduce interface resistances and increase specific capacitances and energy densities. According to the thought of materials design，we will choose a combination of high capacitance, easy-growing and controllable materials. First the two dimensional V2O5 nanobelt arrays grow directly on current collector, and then another kind of compound semiconductor is prepared on the V2O5 nanobelt arrays to form a heterojunction. These new heterojunction not only have one's own advantages, but also significantly enhance electron mobility. In this project, we will propose a low-cost method to prepare high specific capacitance V2O5-based compound semiconductor heterojunction nano-arrays. The synergistic effect and failure mechanism of the heterojunction will be systematically investigated to deepen the understanding of academic and experimental gist for enhancing specific capacitances, energy densities and power densities of supercapacitive electrode materials.