CAREER: Highly-ordered Electrode/Catalyst Assembly in Proton Exchange Membrane Fuel Cells for Enhanced Catalyst Utilization

燃料电池被认为是化石燃料动力应用的有前途的、环保的替代品，特别是在交通运输方面。在这一领域已经进行了大量投资，但经济型燃料电池仍然是一个目标。限制燃料电池装置广泛部署进展的一个关键因素是所掺入的铂催化剂纳米颗粒的高昂成本。宾夕法尼亚州费城德雷克塞尔大学的Vibha Kalra教授将尝试在质子交换膜(PEM)燃料电池中使用一种独特的纳米纤维催化层来改变这一状况。催化剂将通过一种名为静电纺丝的工艺制造。静电纺丝是一种简单的纤维形成技术，它使用强大的电场来加速和稀释聚合物溶液/熔体喷射，从而生成直径为纳米级(50-500 nm)的纤维。该项目将包括实验和多尺度模拟，以首先了解和定制拟议催化剂层的内部组装，然后详细调查这种纳米级组装对燃料电池性能的影响。其目的是在催化层内形成一个相互缠绕的网络，以便催化剂(铂)纳米颗粒能够同时访问所有反应物，以便有效地进行电化学反应。这将最大化电化学表面积，从而最大限度地利用催化剂纳米颗粒，从而降低催化剂的总成本。该项目的综合教育目标是帮助K-12、本科生和研究生，特别是妇女和来自代表性不足的少数群体的学生，认识到科学和工程的力量，并激励他们通过继续研究材料和可再生能源来为社会作出贡献。卡拉教授将为费城地区的学生和教师开发一个全面的K-12推广计划，包括研讨会和研究经验，目前费城地区80%的学生是少数族裔。综合教育活动将在不同教育水平的更多受众中激发对材料和能源研究的兴趣。

ABSTRACTFuel cells are seen as promising, environmentally desirable alternatives to fossil fuel powered applications, particularly for transportation. Significant investments have been made in this area, but economical fuel cells remain a target. A key factor that has limited the progress in broad deployment of fuel cell devices is the high cost of the incorporated platinum catalyst nanoparticles. In this Faculty Early Career Development (CAREER) Program award, Professor Vibha Kalra of Drexel University, Philadelphia, PA will attempt to change this situation using a unique nanofiber-based catalyst layer in proton exchange membrane (PEM) fuel cells. The catalyst will be fabricated via a process called electrospinning. Electrospinning is a simple fiber formation technique that uses strong electric field to accelerate and thin a polymer solution/melt jet, resulting in fibers with nanoscale diameters (50-500 nm). The project will involve experiments and multi-scale simulations to first understand and tailor the internal assembly in the proposed catalyst layer followed by a detailed investigation of the effect of this nanoscale assembly on performance in fuel cells. The aim is to develop an intertwined network within the catalyst layer, such that the catalyst (platinum) nanoparticles have simultaneous access to all reactants for the electrochemical reaction to take place efficiently. This will maximize the electrochemical surface area and consequently the utilization of catalyst nanoparticles, thereby resulting in lower total catalyst cost. The integrated educational objective of this project is to help students at K-12, undergraduate and graduate levels, particularly women and those from under-represented minorities, to appreciate the power of science and engineering in general and to inspire them to contribute to society through continued research in materials and renewable energy. A comprehensive K-12 outreach program will be developed by Prof. Kalra, involving workshops and research experience for students and teachers in the Philadelphia area, where currently 80% of students are minorities. The integrated educational activities will generate interest in materials and energy research among a much larger audience at various education levels.