EAGER: Layered Nanotube Composite Electrodes for Energy Storage

该奖项是根据2009年美国复苏和再投资法案（公法111-5）资助的。本研究将研究在概念验证纳米结构电极中发生的电化学过程，该电极使用由逐层（LbL）组装技术和纳米模板组成的集成方法创建。概念验证电极将在纳米管几何结构中包含锂电池插入阴极材料、离子导电聚合物和电子导电聚合物的环形层。LbL组装是将带相反电荷的物质顺序吸附到底物上（在这种情况下，是纳米孔模板）。这种组合的加工技术赋予了一种层次结构，在这种结构中，材料的性质和三维几何形状在多个长度尺度上可以得到很好的控制。与平面LbL膜电极相比，这种设计有望产生更短的反应扩散路径长度，增加表面积，提高电极利用率。由此产生的纳米结构阴极相对于传统的平面电极，在比能量、功率密度和稳定性方面将取得突破。因此，这项研究不仅有助于科学地理解纳米结构电极中的电化学过程，而且有助于有效储能介质的持续发展。智能优点：更小，更轻，能量密度高的电源是小型应用的理想选择，如便携式电子设备和微机电系统。一个巨大的挑战是创造一个比要供电的设备更小的电源；当应用接近微到纳米尺度时，这一点尤为重要。PI的长期目标是什么？S实验室的目标是通过硬材料和软材料的定向组装来创造微到纳米级的电源。作为初步的努力，这个EAGER项目的目标是创建一个概念验证阴极，其中纳米管阵列充当小规模的阴极森林。最初的挑战包括材料在模板孔的有限尺寸内的定向吸附，以及对纳米管表面电化学反应扩散过程的理解。该项目的成功为纳米管电池的发明铺平了道路，在纳米管电池中，每个组件（阳极、电解质和阴极）都是通过LbL组装和纳米模板依次沉积的。该研究的更广泛影响是创造了一类新的分层制造材料，其中展示了对多个长度尺度的控制。所谓的？分层纳米管吗?将包含紧密界面材料的环形层，每个层执行指定的功能（锂嵌入，离子传导，电子传导，机械加固）。这个概念可以从电化学扩展到反应/分离过程，其中一层可以催化反应，下一层可以分离产物，或者药物传递，每个环状层可以传递特定的药物或结合到特定的受体位点。的吗?大的照片吗?PI的目标是创建和使用多层多功能纳米结构，可以在微纳米尺度上执行一系列任务。通过将该系统应用于锂离子电池，该研究旨在解决越来越小的应用中对有效能量介质不断扩大和多样化的需求。这项工作的结果将通过期刊文章和会议记录广泛传播。上述系统的简化版本将整合到课堂和推广活动中，用于教授学生电化学基础和原理。

0938842LutkenhausThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).This research will investigate electrochemical processes occurring within proof of concept nanostructured electrodes created using an integrated approach consisting of layer-by-layer (LbL) assembly technique and nanotemplating. The proof-of-concept electrodes will contain annular layers of lithium battery intercalation cathode material, ion conducting polymer, and electron conducting polymer within a nanotube geometry. LbL assembly is the sequential adsorption of oppositely charged species to a substrate (in this case, a nanoporous template). The combined processing techniques impart a hierarchical structure where materials properties and three-dimensional geometry at multiple length scales can be finely controlled. Such a design is expected to produce shorter reaction-diffusion path-lengths, increased surface area, and increased electrode utilization relative to planar LbL film electrodes. The resulting nanostructured cathode will represent a breakthrough in specific energy, power density, and stability relative to conventional, planar electrodes. Thus, the research will contribute not only to scientific understanding of electrochemical processes in nanostructured electrodes, but to the continued development of effective energy storage media.Intellectual Merit: Smaller, lighter, energy dense power sources are desired for small-scale applications such as portable electronics and miroelectromechanical systems. A great challenge is to create a power source smaller than the device to be powered; this is especially important as the application approaches the micro- to nanoscale. A long term goal of the PI?s lab is to create micro- to nanoscale power sources from the directed assembly of hard and soft materials. As a preliminary effort, this EAGER project targets the creation of a proof-of-concept cathode, where nanotube arrays act as small-scale cathode ?forests?. Initial challenges include the directed adsorption of materials in the confined dimensions of a template pore, and the understanding of electrochemical reaction-diffusion processes at the nanotube surfaces. Success of this project paves the way for the creation of a nanotube battery, where each component (anode, electrolyte, and cathode) is sequentially deposited using LbL assembly and nanotemplating.The broader impact of the research is the creation of a new class of hierarchically manufactured materials, where control over multiple length scales is demonstrated. The so-called ?layered nanotubes? will contain annular layers of intimately interfaced materials, each performing a designated function (lithium intercalation, ion conduction, electron conduction, mechanical reinforcement). This concept can be extended beyond electrochemistry to reaction/separation processes, where one layer could catalyze a reaction and the next layer could separate the products, or to drug delivery where each annular layer could deliver a specific drug or bind to a specific receptor site. The ?big picture? goal of the PI is to create and use multi-layered multifunctional nanostructures that can perform a sequential set of tasks at the micro- to nanoscale. By applying this system to lithium-ion batteries, the research aims to address the expanding and varied needs of effective energy media for ever-smaller applications. The results of this work will be broadly disseminated through journal articles and conference proceedings. A simplified version of the system described above will be integrated into classroom and outreach activities for teaching students about electrochemistry fundamentals and principles.