SBIR Phase I: Nano-Porous Silicon Gas Diffusion Electrode for Miniaturized Fuel Cells

这个小型企业创新研究（SBIR）第一阶段项目致力于制造微型和纳米加工的硅气体扩散电极（GDE），用于小型化质子交换膜（PEM）燃料电池。 新的微米和纳米加工技术将使薄膜无机膜的应用，从而实现小型化和消除甲醇渗透。典型的PEM燃料电池围绕膜电极组件（MEA）设计，其中膜是自支撑机械构件。目前最先进的PEM燃料电池应用相对厚的NAFION或其他有机材料膜，在高温和高压下将GDE压到每一侧上以形成MEA。将对机械支撑的要求从膜转移到GDE之一允许膜被制成薄达两个数量级。这种方法为新的膜材料和燃料电池的小型化开辟了广阔的可能性，以满足应用需求。 薄膜材料以前没有被用作电解质膜，因为在多孔GDE上施加薄膜的集成问题尚未解决。 该项目将证明，一个GDE与薄膜膜可以构建从微和纳米加工硅，与硅GDE提供所需的机械支持。 商业上，PEM燃料电池用于从运输到个人电子产品的应用。目前，燃料电池在便携式电子设备如手机、笔记本电脑或PDA上的应用很大程度上受到难以实现必要的小型化的限制。所提出的技术将最终实现燃料电池与任何集成电路的集成。这为小型化自主系统创造了全新的可能性。纳米多孔硅技术的其他应用是电化学传感器、SOFC燃料电池、热管理、光发射、吸收和检测设备。 在这项工作中，硅是一种理想的材料选择，具有优异的电气和机械性能，允许应用为半导体电子工业开发的设备，设施和工艺来制造小型燃料电池。由于半导体制造商实行标准化的原则，很可能开发的工艺将被采用和广泛传播。

This Small Business Innovation Research (SBIR) Phase I project addresses fabrication of micro- and nano-machined silicon gas diffusion electrodes (GDEs) for miniaturized Proton Exchange Membrane (PEM) fuel cells. Novel micro- and nano-machining techniques will enable application of thin-film inorganic membranes with resultant miniaturization and elimination of methanol crossover. The typical PEM fuel cell is designed around a Membrane Electrode Assembly (MEA) in which the membrane is a self-supporting mechanical member. Current state-of-the-Art PEM fuel cells apply relatively thick membranes of NAFION or other organic materials, with GDEs pressed onto each side at high temperatures and pressures to form the MEA. Shifting the requirement for mechanical support from the membrane to one of the GDEs allows the membrane to be made up to two orders of magnitude thinner. This approach opens up broad possibilities for new membrane materials and miniaturization of fuel cells to meet application needs. Thin-film materials have not previously been applied as electrolytic membranes because the integration problems of applying thin films over porous GDEs have not been solved. This project will demonstrate that a GDE with thin-film membrane can be constructed from micro- and nano-machined silicon, with the silicon GDE providing the required mechanical support. Commercially, PEM fuel cells are used in applications ranging from transportation to personal electronics. Current applications of fuel cells to portable electronic devices such as cell phones, laptops or PDAs are limited largely by the difficulty in achieving the necessary miniaturization. The proposed technology will ultimately enable integration of fuel cells with any arbitrary integrated circuit. This creates entirely new possibilities for miniaturized autonomous systems. Additional applications for nanoporous silicon technology are electrochemical sensors, SOFC fuel cells, thermal management, light emission, absorption and detection devices. In this work, silicon is an ideal choice of material with excellent electrical and mechanical properties, allowing application of equipment, facilities and processes developed for the semiconductor electronics industry to fabrication of miniaturized fuel cells. Due to the discipline of standardization practiced by semiconductor fabricators, it is likely that developed processes will be adopted and widely disseminated.