In situ X-ray spectromicroscopy study of bipolar plate material stability for nano-fuel-cells with ionic-liquid electrolyte

This paper reports a pioneering application of soft X-ray imaging and spectromicroscopy to a hot material stability issue in fuel-cell (FC) technology: the corrosion of metallic bipolar plates in ionic-liquid-based nano polymer electrolyte membrane (PEM) FCs. Using the potential of the X-ray scanning microscopy for in situ characterisation of complex multi-material systems in electrochemical environments with sub-micrometer lateral resolution, we study the electrochemical behaviour of Fe electrodes in contact with the room-temperature ionic liquid (RTIL)1-butyl-1-methyl-pyrrolidinium bis (trifluoromethylsulfonyl) amide ([BMP][TFSA]) in a nano fuel-cell fabricated by lithography. Thanks to the properties of this RTIL, an open electrochemical cell could be used in vacuum (10(-6) mbar). The possibility of imaging electrochemically induced morphological features in conjunction with local spectroscopic analysis, yields details of the space distribution and chemical correlations of the corrosion products. (C) 2010 Elsevier B.V. All rights reserved.