STXM Characterization of Nanostructured Thin Film Anode Before and After Start-Up Shutdown and Reversal Tests

Nanostructured thin film (NSTF) catalysts are promising for proton exchange membrane fuel cell applications. We have used synchrotron based scanning transmission soft X-ray microscopy (STXM) to evaluate composition and structure of NSTF anodes prepared by decaling and the changes that occur after start-up shut-down and reversal testing. We find the metal decorated perylene red support material is mechanically compressed, so that there is very little penetration of the catalyst into the membrane. Such a structure exhibits little or no chemical modification upon generating the PEM-FC structure. In contrast, after the testing there is essentially no perylene red material detected. However, there is no evidence that the loss of the perylene red support affects the catalytic properties of the anode NSTF structure.