EAGER: Continuous, Catalyzed Thermopower Wave Generators Powered by Renewable Biofuels: A New Fuel Cell Concept

EAGER：由可再生生物燃料驱动的连续催化热电波发生器：一种新的燃料电池概念

• 批准号: 1239073
• 负责人: Michael Strano
• 金额: $ 8.15万
• 依托单位: Massachusetts Institute of Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-08-15 至 2013-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1239073&HistoricalAwards=false
• 关键词: EAGER; Continuous; Catalyzed; Thermopower; Wave

Abstract#1239073Strano, Michael S.Technical BasisPortable energy storage and delivery is the cornerstone of modern transportation systems and the of the proliferation of portable electronic devices and is a rapidly growing field. Additionally, the development of the newest autonomous and mobile sensors, robots, and off-grid wireless networks, particularly at the micro- and nanoscale, is often hampered today by the lack of high power density energy systems of similar size. Each of todays portable energy technologies has its distinct shortcomings. Batteries are the most familiar form of electrical energy storage, but electrochemical energy density is fundamentally limited compared to storing energy in the chemical bonds of fuels. In addition, batteries slowly lose their charge over years, making them less desirable for long-term energy storage. Supercapacitors offer substantially higher power density (in weight and volume terms), but at the expense of energy density. Moreover, they cannot hold their charge even as long as batteries. Fuel cells and engines can use the large energy density of chemical fuels but are more complicated to fabricate at the small scale, so their power density has been limited so far. Professor Michael Strano of the Massachusetts Institute of Technology has performed some initial studies on an alternative energy device that offers the possibility of supplanting these existing devices.Thermopower wave based energy devices may dramatically increase the energy density of portable power devices more than a factor of 10, with other advantages such as zero storage losses and charge decay. High-conductivity scaffolds, like carbon nanotubes (CNTs), direct a hot chemical reaction wave along their length; the wave also pushes charge carriers to create a high-power pulse of electricity. This fast wave means that thermopower waves can often outperform conventional thermoelectrics using static thermal gradients in terms of power density and may not have the same limits on efficiency (usually about 1-5%)according to Strano. The concept to be tested is whether thermopower fuel cells can be created, which could be operated to generate power continuously; previous devices could only make electrical pulses shorter than a second. This project introduces the new aspect of the addition of metal catalyst nanoparticles to the CNT thermoelectric conduits. By focusing on fuels like formic acid and methanol that can be biologically derived, these generators can use renewable energy sources. This is an ideal EAGER project in that several high risk aspects must be successfully demonstrated. First, wave propagation using formic acid and alternatively methanol must be demonstrated using low- to medium-activity catalytic materials for their decomposition along the length of thermal conduit materials, including carbon nanotube fibers, inorganic nanowires, or grapheme films. Advances in theoretical understanding of these waves will accompany this effort. The choice of catalyst(s) must optimize the activation energy; too low and the fuel will react spontaneously without being controlled by the nanotubes, too high and the required initiation energy will be too large, sapping the efficiency. For liquid-fueled-TWGs to be practical, more common metals like Au, Fe, or Cu must be the active catalyst metal. Beyond this, a target would be to fabricate a working device and demonstrate extended operating life. This is clearly the high risk-high potential return project envisioned for EAGER awards. Broader Impacts For this project, the PI intends to utilize undergraduate and graduate researchers, as a means of fostering diversity in Engineering. The PI notes that the experiments that make up this project seem to be well suited for undergraduates, who adapt and learn quickly how to prepare thermopower wave substrates, and learn how to use the instrumentation. The PI has extensively worked with a large body of undergraduate students in the past, many of whom are gender and racial minorities. It is difficult to develop these aspects in a short EAGER project, so the PI is to be commended for making this effort.

摘要#1239073Strano, Michael S.技术基础便携式能量存储和传输是现代交通系统和便携式电子设备激增的基石，是一个快速发展的领域。此外，由于缺乏类似尺寸的高功率密度能源系统，最新的自主和移动传感器、机器人和离网无线网络的开发，特别是在微米和纳米尺度上，常常受到阻碍。当今的每一种便携式能源技术都有其独特的缺点。电池是最常见的电能存储形式，但与燃料化学键中存储的能量相比，电化学能量密度从根本上是有限的。此外，电池会随着时间的推移慢慢失去电量，使其不太适合长期储存能量。超级电容器提供更高的功率密度（在重量和体积方面），但代价是能量密度。此外，它们甚至无法像电池一样长时间保持电量。燃料电池和发动机可以利用化学燃料的高能量密度，但小规模制造起来比较复杂，因此迄今为止它们的功率密度受到限制。麻省理工学院的 Michael Strano 教授对替代能源设备进行了一些初步研究，该设备提供了替代这些现有设备的可能性。基于热电波的能源设备可以将便携式电源设备的能量密度显着提高 10 倍以上，并具有零存储损耗和电荷衰减等其他优点。高电导率支架，如碳纳米管（CNT），沿着其长度引导热化学反应波；该波还推动电荷载流子产生高功率脉冲。根据 Strano 的说法，这种快速波意味着热电波在功率密度方面通常可以优于使用静态热梯度的传统热电波，并且可能没有相同的效率限制（通常约为 1-5%）。测试的概念是能否制造出热电燃料电池，使其能够持续发电；以前的设备只能使电脉冲短于一秒。该项目引入了在碳纳米管热电导管中添加金属催化剂纳米粒子的新方面。通过专注于甲酸和甲醇等可生物衍生的燃料，这些发电机可以使用可再生能源。这是一个理想的 EAGER 项目，因为必须成功证明几个高风险方面。首先，必须使用低活性到中等活性的催化材料来证明使用甲酸和甲醇的波传播，以沿着热导管材料（包括碳纳米管纤维、无机纳米线或石墨烯薄膜）的长度进行分解。对这些波的理论理解的进步将伴随着这一努力。催化剂的选择必须优化活化能；太低，燃料将自发反应，不受纳米管控制；太高，所需的引发能量太大，从而降低效率。为了使液体燃料 TWG 实用化，更常见的金属（如金、铁或铜）必须是活性催化剂金属。除此之外，目标是制造一个工作装置并展示更长的使用寿命。这显然是EAGER奖项所设想的高风险高潜在回报项目。更广泛的影响 对于这个项目，PI 打算利用本科生和研究生研究人员作为促进工程多样性的一种手段。 PI 指出，组成该项目的实验似乎非常适合本科生，他们可以快速适应并学习如何准备热电波基底，并学习如何使用仪器。 PI 过去曾与大量本科生进行过广泛合作，其中许多人是性别和种族少数群体。在一个简短的 EAGER 项目中很难开发这些方面，因此 PI 所做的努力值得赞扬。