Luminescent sensory polymer coating composed of platinumporphyrin and poly(trimethylsilylpropyne) for real-time oxygen visualization in operating PEFCs

A luminescent PtTFP/PMSP polymer coating was prepared for the oxygen partial pressure visualization inside a PEFC. PMSP formed a smooth and tough coating as a highly oxygen-permeable matrix with a thickness of ca. 2 μm in which the PtTFP was homogeneously dispersed. The coating displayed a strong red luminescence with significantly decreasing intensity upon increasing oxygen partial pressure. The sensitivity for the oxygen partial pressure was high and the analytical curve of the sensor polymer coating was undisturbed by external factors. The PtTFP/PMSP sensor was coated on the surface of a cathode gas diffusion layer on the air flow channel inside PEFC. The oxygen-pressure distribution in the air flow channel was successfully visualized while operating the PEFC. A luminescent sensory polymer coating was prepared for the visualization of the oxygen partial pressure in the interior of the cathode separator channels of an operating fuel cell. The coating was stable under irradiation in water, acids, and methanol at high temperatures. The oxygen distribution on the surface of the channel was successfully visualized in real-time through analysis of luminescence and quenching.