Ultrasensitive Contaminant Detection for PEM Fuel Cell Hydrogen Feed Strain

Hydrogen fuel cells are poised to replace the internal combustion engine in the future. One example is a proton exchange membrane (PEM) fuel cell that operates at low temperature and high power densities making them ideal candidates for automobile and other small domestic power applications. The main drawback of the technology is that PEM cells require highly pure hydrogen are easily poisoned by sulfur containing species and other impurities. A typical source of hydrogen for the Military is fuel reformers using fuels such a JP8. These feed stocks may contain compounds in trace amounts that would foul catalysts. Lynntech will develop an ultrasensitive sensor for liquid or vapor assuring the purity of the H2 feed streams or reformer intake. The technology relies on whispering gallery modes (WGM); optical resonances in micron-sized spheres that, due to the high quality factor, are extremely sensitive to the environment around the resonator. This property is detrimental to most sensing applications but can be used advantageously to detect minute changes in the hydrogen feed stream or reformate stock. To impart chemical sensitivity, microresonators will be coated with nanoparticles of the catalyst material or other metals to provide an exact representation and test for fouling compounds.