Grant: Research Tools and Instruments

While the global CO2 emissions continue to rise, transportation-related energy consumption remains as one of the largest contributors to the global emissions. Proton exchange membrane fuel cells (PEMFCs) are an attractive alternative to internal combustion engines for automotive applications, due to their ability to produce on-demand electricity with zero local carbon emissions. By using H2 produced from clean energy sources (via electrolysis) as fuel, PEMFCs can decarbonize the transportation sector. PEMFCs are particularly attractive for replacing heavy duty vehicle (HDV) engines, since PEMFCs feature long driving range, fast refueling time, and low weight and size relative to competing clean energy technologies. However, HDVs demand a lifetime approximately 6.5 times longer than that of passenger vehicles, necessitating improvements in the durability of PEMFCs for their wider adoption in the HDV industry. The main contributors to the insufficient durability of PEMFCs are catalyst layer-related degradation modes, such as loss of catalyst and leaching of catalyst alloys. Specifically, catalyst dissolution during prolonged operation leads to a decrease in the catalyst mass loading in the catalyst layer. Additionally, leaching of alloy elements from catalysts reduces the catalyst mass activity and increases ion generation that can contaminate the catalyst layer. Overall, these undesired modes of degradation lead to decrease in energy efficiency of PEMFCs. Although many previous studies have elucidated the underlying mechanisms of these degradation modes, these degradation modes are inherently heterogeneous across the catalyst layer of PEMFC, but how this heterogeneity affects the overall energy efficiency of PEMFCs remain poorly understood. Prof. Lee is requesting funds to purchase a two-dimensional micro-X-ray fluorescence (2D µXRF) spectrometer, capable of mapping metal and metal ion distributions across the catalyst layer. This equipment will be coupled with Prof. Lee's electrochemical testing capabilities to elucidate comprehensive understanding of heterogeneous degradation modes in PEMFCs. Two sub-objectives will be accomplished: (1) measurement of local platinum loss from the catalyst layer after accelerated stress tests, and (2) characterization of cobalt ion mobility in catalyst layers through ex situ cation migration test. The results will inform operating condition and material design strategies to mitigate energy efficiency loss of PEMFCs for HDV applications. This equipment will provide Prof. Lee and his group with a unique capability for comprehensive analysis of heterogeneous degradation modes in PEMFC catalyst layers, and will equip HQPs with highly competitive skills that will attract employers from industry. Also, the outcomes of this research will attract collaborations with leading industrial partners such as Cummins and Ballard, and strengthen Canada's leadership in hydrogen fuel cell technologies.