CAREER: Multicomponent Transport in Polymer Electrolyte Membranes

Drexel University, Philadelphia PA

Investigators

Abstract

PROPOSAL NUMBER: CBET-0644593 PROPOSAL TYPE: CAREER PRINCIPAL INVESTIGATOR: YOSSEF ELABD AFFILIATION: DREXEL UNIVERSITY PROPOSAL TITLE: CAREER: MULTICOMPONENT TRANSPORT IN POLYMER ELECTROLYTE MEMBRANES Fuel cells offer an innovative and environmentally benign alternative to current power sources. In particular, the proton-exchange membrane (PEM) fuel cell has generated interest for large market applications, such as transportation. A key element in this fuel cell is the PEM, which serves as an electrolyte, exchanging protons from the anode to the cathode to derive electrical energy directly from a chemical fuel; however, the PEM is also the component that contributes to significant power and efficiency losses. Intellectual Merit: The objective is to study multicomponent transport phenomena in PEMs on a molecular scale using time-resolved Fourier transform infrared-attenuated total reflectance (FTIR-ATR) spectroscopy. The outcomes of this research project will provide a fundamental understanding of multicomponent transport mechanisms and provide a new body of knowledge in fuel cell research. This information will be used to develop new membranes with improved fuel-cell performance. Time-resolved FTIR-ATR spectroscopy distinguishes itself from other techniques because of its ability to sensitively differentiate between various chemical components by providing molecular-level contrast between diffusants and the polymer in real time based on absorbing light at different wavelengths or vibrational bond energies. The technique not only can quantify multiple diffusing components simultaneously, but also can quantitatively measure molecular interactions between diffusants and the polymer through shifts in the infrared spectra, which is exclusive to this technique. This proposed work will answer a number of fundamental transport questions directly linked to key problems with fuel cells: low proton conductivity at high temperatures and low humidities (hydrogen fuel cell) and high methanol crossover rates (methanol fuel cells). A comprehensive plan is proposed, where the PI will first measure and understand multicomponent transport mechanisms in PEMs and design and test new PEMs for improved fuel-cell performance. Preliminary data recently collected in the PI's laboratory: (1) water vapor transport measurements and (2) liquid methanol/water mixture transport measurements in Nafion membranes with time-resolved FTIR-ATR spectroscopy and the (3) development and testing of new PEM blend membranes with improved methanol fuel cell performance, provide a sound framework for the proposed research plan. Broader Impacts: The PI proposes two new programs that will focus on the integration of education and research at both the K-12 and undergraduate level. The first program is for underprivileged (low income families) and underrepresented (minorities) students, specifically students from five Philadelphia city high schools. This program will provide engineering education and an opportunity to disseminate fuel-cell technology and research results through a week-long summer program with hands-on laboratories, projects, demonstrations, and presentations. The second program is a new co-operative (co-op) undergraduate research program that will encourage more undergraduates to pursue research as an alternative to Drexel's traditional industrial non-research based co-op program. This new program is a Drexel-DuPont partnership, where the undergraduate students involved will experience research both in an academic and industrial setting. These programs will provide avenues for the dissemination of fuel-cell research to underprivileged and underrepresented groups at the K-12 level and stimulate more undergraduate research at Drexel.