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

Ananaerobic transfer electrochemical cell, mounted on a side arm of th e UHV chamber at 90-degrees to the fast entry lock system of the XPS i nstrument was used to study the base-salt transitions in the three mai n forms of PANI (leucoemeraldine, emeraldine and pernigraniline). The curve analyses of the N 1s peak, cross-checked with relative atomic ra tios of different species, are used to gain an understanding of the su rface chemistry of the various PANI forms. Parallel analyses, using an ex situ cell, are performed. The results obtained highlight the air s ensitivity of base leucoemeraldine and confirm the possibility of obta ining, using an ATE cell, electrochemical surfaces which, when analyse d by XPS, display the surface chemical composition they are expected t o have in the cell. Nevertheless this approach is not free from experi mental difficulties especially as far as designing and mounting of the sample/electrode is concerned.