Collaborative Research: Self-Sustaining Thermochemical Pumping and Power Generation At Mesoscales

CBET-1403405/1402142 Ahn（锡拉丘兹）/Ronney（USC）便携式电子设备（PED），如手机和笔记本电脑，对电力的需求不断增长，但它们使用的电池每磅只能提供1%至2%的能量作为碳氢化合物燃料。 由于碳氢燃料具有高能量密度，因此它们是大规模发电的首选燃料。 然而，这并不是在小规模上完成的，因为工程师们无法将内燃机或蒸汽机的规模缩小到为PED发电所需的尺寸。 微型燃料电池（将燃料直接转化为电力）已被用于为PED提供动力，但仅通过使用具有安全问题和/或当包括存储罐的重量时每磅能量非常低的燃料如氢或甲醇而成功。 目前的工作提出使用丙烷和丁烷，在一次性打火机中使用的相同的易于储存的高能量密度燃料，用于为PED发电，并提供了一个非常简单的，多功能的系统，用于供应空气的设备。 这项工作的结果可能会对电能存储密度超过电池10倍的PED产生重大影响。 此外，在垃圾填埋场处理空燃料盒比处理含有有毒金属的旧电池更可取。 这项工作将涉及本科生和研究生工程专业的学生，并通过锡拉丘兹和南加州大学的项目教育K-12学生。便携式电子设备对电力的需求不断增长，但电池提供的能量密度仅为碳氢燃料的1%至2%。 将内燃机和发电机按比例缩小到MEMS规模一直不成功，这是由于热损失、摩擦以及难以以足够的精度在小规模下制造零件的问题。 PI建议使用（1）用于燃料和空气泵送的纳米多孔材料中的热蒸发;（2）具有室温点火的Pt-和Au-催化剂上的燃烧;和（3）单室固体氧化物燃料电池，其不需要在热蒸发泵内的燃料和用于发电的氧化剂之间的密封或分离，以小规模从烃燃料产生电力。 任意形状的反应器将使用多孔烧结不锈钢的独特三维打印技术构建的部件来构建。 负载型Au纳米粒子的碳氢化合物氧化的低温点火活性将使用原位FTIR/气相色谱分析来测量。 为了确定什么性质对低温氧化影响最大，将通过扫描电子显微镜评估其表面结构改性，并通过X射线光电子能谱评估其化学改性。 离子取代对双钙钛矿结构的性能的影响将被研究，几种贵金属，氧化物负载的电催化剂的催化行为也将被检查。 高纯度的氧化钆掺杂的氧化铈源有望提高电解质的电导率，但仍保持薄膜电解质燃料电池制造的可加工性。 设想的系统是独立的，具有集成到一个装置中的泵送和发电，没有移动部件并且仅依靠由烃燃料（即，它没有寄生电能损耗）。 这项研究还可以将其应用于需要气体加压或真空泵的其他系统，例如微型气相色谱仪或有毒化学试剂传感器。

CBET-1403405/1402142Ahn (Syracuse)/Ronney (USC)Portable electronic devices (PEDs) such as cell phones and laptop computers have ever-growing needs for electrical power, yet the batteries they use provide only 1 to 2% energy per pound as hydrocarbon fuels. Because hydrocarbon fuels pack high energy densities, they are the fuel of choice for power generation at large scales. However, this is not done at small scales since engineers have been unable to scale internal combustion or steam engines down to the sizes required to generate electricity for PEDs. Tiny fuel cells (which convert fuel directly into electricity) have been used to power PEDs, but have only succeeded by using fuels such as hydrogen or methanol which have safety issues and/or very low energy per pound when the weight of the storage tank is included. The present work proposes to use propane and butane, the same easily-stored, high energy density fuels used in disposable lighters, for generating power for PEDs and provides a very simple, versatile system for supplying air to the device. The results of this work could have a significant impact on PEDs with electrical energy storage densities exceeding batteries by a factor of 10. Moreover, disposal of empty fuel cartridges in landfills is preferable to disposal of used batteries containing toxic metals. This work will involve undergraduate and graduate engineering students and also educate K-12 students through programs at Syracuse and USC.Portable electronic devices have ever-growing needs for electrical power, yet batteries provide only 1 to 2% of the energy density of hydrocarbon fuels. Scale-down of internal combustion engines and electrical generators to MEMS scales has been unsuccessful due to issues with heat losses, friction and the difficulty of manufacturing parts at small scales with sufficient precision. The PIs propose to generate electrical power from hydrocarbon fuels at small scales using (1) thermal transpiration in nanoporous materials for fuel and air pumping; (2) combustion on Pt- and Au- catalysts with room-temperature ignition; and (3) single-chamber solid oxide fuel cells requiring no seals or separation between fuel and oxidant for power generation within the thermal transpiration pump. Reactors of arbitrary shape will be constructed using parts built using a unique 3-dimensional printing technology for porous sintered stainless steel. The activity of supported Au nanoparticles for low-temperature ignition of hydrocarbon oxidation will be measured using in-situ FTIR/Gas Chromatography analysis. To determine what property has the most impact on low-temperature oxidation, their surface structure modifications will be assessed via Scanning Electron Microscopy and their chemical modifications via X-ray Photoelectron Spectroscopy. The effects of ion substitution on the properties of double-perovskite structures will be investigated and the catalytic behavior of several precious-metal, oxide-supported electrocatalysts will also be examined. A high purity source of gadolinia-doped-ceria is expected to increase the electrolyte conductivity, yet retain the processability for thin-film electrolyte fuel cell fabrication. The envisioned system is self-contained, has pumping and power generation integrated into one device, has no moving parts and operates only on thermal and electrochemical energy supplied by hydrocarbon fuels (i.e., it has no parasitic electrical energy losses). This research could also enable spin-off applications to other systems requiring gas pressurization or vacuum pumping, e.g. micro gas chromatographs or toxic chemical agent sensors.