THE USE OF THE ANAEROBIC TRANSFER ELECTROCHEMICAL-CELL IN THE XPS INVESTIGATION OF POLYANILINE

Ananaerobic transfer electrochemical cell, mounted on a side arm of the UHV chamber at 90-degrees to the fast entry lock system of the XPS instrument was used to study the base-salt transitions in the three main forms of PANI (leucoemeraldine, emeraldine and pernigraniline). The curve analyses of the N 1s peak, cross-checked with relative atomic ratios of different species, are used to gain an understanding of the surface chemistry of the various PANI forms. Parallel analyses, using an ex situ cell, are performed. The results obtained highlight the air sensitivity of base leucoemeraldine and confirm the possibility of obtaining, using an ATE cell, electrochemical surfaces which, when analysed by XPS, display the surface chemical composition they are expected to have in the cell. Nevertheless this approach is not free from experimental difficulties especially as far as designing and mounting of the sample/electrode is concerned.