Hybrid Carbon-Polymer Supercapacitors for High Energy Storage and Power Delivery

该项目旨在开发增强型储能装置，特别是超级电容器，可以储存大量能量或按单位重量充电，并以高功率输送。储存大量电荷的能力将使它们能够用于高需求的应用，如电动和混合动力汽车。高功率将确保这些设备可以快速充电，充电时间从几秒到几分钟不等(不像充电电池需要几个小时才能充电)。例如，储能属性的潜在改进将对支持电动汽车的技术做出非常重要的贡献。该项目将为两名博士研究生和几名本科生提供纳米材料和可再生能源的跨学科教育经验。本项目的具体研究目标是制备并研究由多孔碳-电活性聚合物核壳纳米纤维组成的新型杂化超级电容器电极的工艺-结构-性能相关性。制造将通过一个简单的两步过程进行。在第一步中，碳前体和牺牲聚合物两种聚合物的共混纳米纤维将通过静电纺丝和高温热解来制备，将碳前体转化为碳并分解出牺牲聚合物，从而得到具有高比表面积(1500 m2/g)的分级多孔碳纳米纤维。在第二步中，利用一种新的“无液体”化学气相沉积(CVD)方法，将多孔碳纳米纤维收缩包裹在由噻吩基、吡咯或苯胺组成的超薄外壳中。其目的是将多孔碳纳米纤维的双电层电容与薄的共形聚合物涂层的伪电容相结合，以实现协同性能效果，包括优化能量密度和功率传输，以及改善循环性能。与工业合作伙伴的合作将为未来的制造提供一条可行的道路。

This project aims to develop enhanced energy storage devices, in particular, supercapacitors, that can store large amounts of energy or charge per unit weight of the material and deliver them at high power. The ability to store large amounts of charge will enable their use in high-demand applications such as electric and hybrid vehicles. High power will ensure that these devices can be charged at a fast rate with charging times of a few seconds to a few minutes (unlike rechargeable batteries that require several hours for charging). The potential improvement in energy storage attributes will, for example, contribute very significantly to technology that supports electric vehicles. This project will provide two PhD graduate and several undergraduate students with an interdisciplinary educational experience in nanomaterials and renewable energy.The specific research objective of this project is to fabricate and study process-structure-performance correlation in a novel hybrid supercapacitor electrode composed of porous carbon-electroactive polymer core-shell nanofibers. The fabrication will be conducted via a simple two-step process. In Step 1, nanofibers of blends of two polymers; carbon precursor and sacrificial polymer, will be fabricated via electrospinning followed by high temperature pyrolysis to convert the carbon precursor to carbon and decompose out the sacrificial polymer, resulting in hierarchically-porous carbon nanofibers exhibiting high specific surface area (1500 m2/g). In Step 2, the porous carbon nanofibers will be shrink-wrapped with an ultrathin shell of conducting polymer of thiophene, pyrrole or aniline using a novel "liquid-free" chemical vapor deposition (CVD) approach. The aim is integrate electric double layer capacitance from porous carbon nanofibers with pseudocapacitance from thin and conformal polymer coatings to achieve synergistic performance effects including optimized energy density and power delivery and improved cycling performance. Collaboration with industrial partners will enable a feasible path for future manufacturing.