SGER: Optimized Catalyst Layer Structure for PEM Fuel Cells

SGER：用于质子交换膜燃料电池的优化催化剂层结构

• 批准号: 0341271
• 负责人: Trung Nguyen
• 金额: $ 5.06万
• 依托单位: University of Kansas Center for Research Inc
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-10-15 至 2005-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0341271&HistoricalAwards=false
• 关键词: SGER; Optimized; Catalyst; Layer; Structure

The catalyst layer, being the power-producing component, is considered as the most important component in a PEM fuel cell. It is a region where all three important phases must be brought together to enable the power generating reactions to occur. Currently, the catalyst layers in a PEM fuel cell are made of platinum on carbon support, Nafion ionomer and Teflon. The solid Pt/C catalyst phase acts as the electro-catalyst for the hydrogen oxidation or oxygen reduction reactions at the anode and cathode and provides electronic conduction to and from the reactive sites. The Nafion ionic phase provides the ionic conductivity or pathways for the protons to migrate to and from the membrane electrolyte and acts as a binder for the catalyst particles. Teflon creates the hydrophobic gas region for reactant gas transport to and from the catalyst surface within the catalyst layers. To achieve high performance in a PEM fuel cell, the three major sources of voltage loss (activation, ohmic and transport) in a PEM fuel cell must be minimized. The voltage loss due to the activation resistance in the catalyst layer can be reduced by increasing the electro-active catalyst surface area. The voltage loss due to the ohmic resistance can be reduced by increasing the ionic and electronic conduction in the catalyst layer. Finally, the voltage loss due mass transport can be reduced by minimizing the thickness of the region through which the slowest transport process occurs (Nafion film) and minimizing the barriers (like liquid water) to the transport processes of reactants to and from the catalyst surface. The intellectual merit of this proposed process is its ability to create a catalyst layer with well-defined and controlled structure necessary to satisfy the requirements needed to achieve high performance in a PEM fuel cell as described above. If this process is successful, it will result in membrane and electrode assemblies and fuel cells with superior performance. The broader impacts of this work are that the use of fuel cells will help reduce environmental problems and the U.S.'s dependence on foreign oil. Consequently, technology that increases its performance will increase its competitiveness and help accelerate the commercialization of this technology. Furthermore, the process developed here could also be used to create ideal catalyst layer structures for electrodes used in other electrochemical applications.

催化剂层是产生功率的成分，被认为是PEM燃料电池中最重要的组件。 在这个区域，必须将所有三个重要阶段汇集在一起​​以使产生反应的发生。目前，PEM燃料电池中的催化剂层是由碳载体，Nafion Ionomer和Teflon的铂制成的。固体PT/C催化剂相充当阳极和阴极上氢氧化或氧还原反应的电催化剂，并从反应性位点提供电子传导。 Nafion离子相为质子迁移往返膜电解质的离子电导率或途径，并充当催化剂颗粒的粘合剂。 Teflon创建了疏水性气体区域，用于催化剂层中催化剂表面和从催化剂表面转运。 为了在PEM燃料电池中实现高性能，必须最小化PEM燃料电池中电压损耗（激活，欧姆和运输）的三个主要来源。 通过增加电活性催化剂表面积可以降低催化剂层激活层的电压损耗。通过增加催化剂层的离子和电子传导，可以降低由于欧姆电阻引起的电压损耗。最后，可以通过最大程度地减少发生最慢的运输过程（Nafion膜）的区域的厚度，并将屏障（如液态水）最小化到催化剂表面和从催化剂表面的反应物的传输过程来最大程度地减少质量运输的电压损失。 该提出的过程的智力优点在于其能够创建具有明确和控制结构的催化剂层，以满足如上所述在PEM燃料电池中实现高性能所需的要求。 如果此过程成功，将导致膜和电极组件和燃料电池具有出色的性能。 这项工作的更广泛的影响是燃料电池的使用将有助于减少环境问题和美国对外国石油的依赖。因此，提高性能的技术将提高其竞争力并有助于加速该技术的商业化。 此外，此处开发的过程也可用于为其他电化学应用中使用的电极创建理想的催化剂层结构。