Flexible Core/Shell Nanocable - Carbon Microfiber Hybrid Composite Electrodes for High-Performance Supercapacitors

该奖项为在高度柔韧和坚固的碳纤维基板上合成大量导电芯/过渡金属氧化物壳纳米电缆提供了资金。这项工作的主要目标是解决用于便携式电子设备和可穿戴电子设备的超级电容器的三个最关键的限制，即不灵活性，低比电容以及充电/放电循环期间离子插入/提取导致的电极失效。导电芯将用于支持氧化还原活性过渡金属氧化物外壳，具有高度电解可及的表面积，并为外壳提供可靠的电气连接，从而充分利用过渡金属氧化物以及通过电极的快速电子和离子传导。碳微纤维不仅可以为电极提供柔韧性和机械强度，而且比平坦的导电衬底具有更大的表面积，可以生长更多的纳米电缆，从而进一步提高比电容和能量密度。本研究项目将研究在柔性碳微纤维上生长的核/壳纳米电缆的形成机制以及核/壳纳米电缆的电化学储能机制。碳微纤维混合复合电极。通过新颖的层次化纳米/微结构设计，探索高柔性、高比电容、高能量密度、高功率密度、快速充放电速率和长循环寿命的复合电极的高通量制造。如果成功，本研究的结果将有助于更好地理解核/壳的制造-结构-性能-功能？碳微纤维混杂复合材料及其电极。这项研究有可能改变柔性电极设计的传统概念，并对现有的电极制造技术产生重大影响。通过该项目取得的研究进展将产生新的知识，这些知识将通过现有课程介绍给本科生和研究生，研究活动将被用作各级学生学习纳米制造和纳米技术储能系统的教育平台。

This award provides funding for synthesizing large quantities of conductive-core/transition-metal-oxide-shell nanocables on a highly flexible and strong carbon microfiber substrate. The primary goal of this work is to solve the three most critical limitations in supercapacitors for portable electronic devices and wearable electronics, i.e., inflexibility, low specific capacitance, and electrode failure resulting from ion insertion/extraction during charge/discharge cycling. The electrical conductive-cores will be used to support redox active transition-metal-oxide-shells with highly electrolytic accessible surface area and also to provide reliable electrical connections to the shells, enabling full utilization of transitional-metal-oxide and fast electronic and ionic conduction through the electrode. The carbon microfibers will offer not only flexibility and mechanical strength to the electrode but also more surface area than a flat conductive substrate for growing more nanocables, which further improves the specific capacitance and energy density. This research program will study the formation mechanisms of the core/shell nanocables grown on flexible carbon microfibers and the electrochemical energy storage mechanisms of the core/shell ? carbon microfiber hybrid composite electrodes. High throughput manufacturing of such composite electrodes with high flexibility, high specific capacitance, high energy density, high power density, fast charging/discharging rate, and long cycle life will be explored through the novel hierarchical nano/micro architecture design. If successful, the results of this research will contribute to a better understanding of the manufacturing-structure-property-function of the core/shell ? carbon microfiber hybrid composites and their electrodes. This research has the potential to change the conventional concepts for flexible electrode design and to significantly impact existing electrode manufacturing technologies. The research advances made through this project will generate new knowledge that will be introduced to undergraduate and graduate students through existing courses and the research activities will be used as an educational platform for students at all levels to learn about nanomanufacturing and nanotechnology-enabled energy storage systems.