Engineered Fuel Cell Membranes: Multiscale Design and Processing for Multifunctional Performance

智能优点：燃料电池提供了一种高效、清洁和安全的能源转换技术，可以作为减少对化石燃料资源依赖的战略的一部分。质子交换膜燃料电池是固定发电、建筑物分布式电源以及交通和便携式电子应用的轻便便携式电源的首选选择。燃料电池膜的化学和机械降解限制了寿命；目前技术的运行窗口受温度和湿度的限制。这一跨学科研究计划的目标是通过质子交换膜的多尺度设计和加工来实现质子传导性的增强和寿命的改善。为了实现这一目标，将采用一种综合的多尺度材料设计和加工方法，将两种相对较新的加工能力--纳米纤维基质的静电纺丝和聚合物纳米复合薄膜的逐层组装首次结合在一起，以生成多层聚合物膜。通过控制沉积长度为1-100纳米的薄膜结构，在纤维基质上和纤维基质内沉积直径为100-1000 nm的纤维，将制备新型薄膜。这种设计和加工策略提供了同时实现传输路径和长寿命机械完整性的途径。将利用完全耦合的多尺度和多物理建模来理解和指导实现所需的膜的机械、化学和传输特性所需的微结构设计。更广泛的影响：这项研究的基本性质将为设计和加工纳米结构膜提供基础，这些膜旨在为广泛的工程应用实现传输和机械性能的组合。本研究为机械化工专业学生的教育提供了一个跨学科、协作式的团队环境。通过与麻省理工学院材料科学与工程中心的合作，该项目将扩大到全国各地的高中和大学本科生，特别强调代表性不足的群体。该项目将通过麻省理工学院暑期研究计划(MSRP)吸引来访的本科生研究人员，该计划旨在增加未被充分代表的少数族裔学生参与研究，并为他们的研究生学习做好准备。项目教员还为MSRP的学生提供专门的研究研讨会。在研究生阶段，开发了一门关于电化学能量转换基础的课程“电化学系统：原理、材料和技术”，向机械工程、材料科学和工程、化学工程、化学和电气工程的研究生介绍热化学和电化学系统的统一热力学和动力学概念。最后，在校园内外的一些场所，国际学生联合会积极开展对妇女和代表不足的少数族裔学生的教育和辅导活动。

Intellectual Merit: Fuel cells offer an efficient, clean and safe energy conversion technology that can be part of a strategy to reduce the dependence on fossil fuel resources. Proton exchange membrane fuel cells are the preferred alternative for stationary power generation, distributed power in buildings, and lightweight portable power for transportation and portable electronics applications. Chemical and mechanical degradation of fuel cell membranes limit the lifetime; the operating windows of current technology are very restricted in terms of temperature and humidity. The objective of this interdisciplinary research program is to achieve enhancements in proton conductivity together with improvements in lifetime through the multiscale design and processing of proton exchange membranes. This goal will be pursued using an integrated multiscale materials design and processing approach in which two relatively new processing capabilities, electrospinning of nanofiber matrices and layer-by-layer assembly of polymer nanocomposite thin films, will be combined for the first time to generate multilayered polymer membranes.Novel membranes will be fabricated by the controlled deposition of thin film architectures on the 1 to 100 nanometer lengthscale, upon and within fiber matrices with fiber diameters on the 100-1000 nm scale. This design and processing strategy provides avenues to achieve simultaneously transport pathways and long lifetime mechanical integrity. Fully coupled multiscale and multiphysics modeling will be utilized to understand and guide the microstructure designs needed to achieve the desired mechanical, chemical and transport properties of the membranes. Broader Impact: The fundamental nature of this research will provide the basis for the design and processing of nanostructured membranes engineered to achieve combinations of transport and mechanical properties for a wide range of engineering applications. The research provides an interdisciplinary and collaborative team environment for the education of mechanical and chemical engineering students. Through involvement with the MIT Center for Materials Science and Engineering, the project will have outreach to high school and college undergraduates from around the country, with special emphasis on underrepresented groups. The project will engage visiting undergraduate researchers through the MIT Summer Research Program (MSRP); a program designed to increase the participation of underrepresented minority students in research and prepare them for graduate studies. Project faculty also offer specially-geared research seminars to the MSRP students. At the graduate level, a course on fundamentals of electrochemical energy conversion "Electrochemical Systems: Principles, Materials and Technologies" has been developed introducing unified thermodynamic and kinetics concepts for thermo-chemical and electrochemical systems to graduate students from mechanical engineering, materials science and engineering, chemical engineering, chemistry and electrical engineering. Finally, the PI's are actively engaged in educational and mentoring outreach to women and underrepresented minority students in a number of venues on and off campus.