HREELS study of ultra-thin polyaniline films grown on Cu(110) by vapor deposition of aniline tetramers

The physical and chemical properties of polyaniline thin films produced by vapor deposition of aniline tetramers on a Cu(110) substrate have been investigated using high-resolution electron energy loss spectroscopy (HREELS). HREELS spectra showed that aniline tetramers are stable on the Cu(110) surface and do not react to form longer chains. Tetramer films doped with HCl exhibited HREEL spectra with features characteristic of a semiconductor. The physical properties of the tetramer films have also been compared to those of films grown by exposing Cu(110) to aniline oligomers produced via pyrolysis of bulk emeraldine. Those films exhibit thickness-dependent changes related to reactivity of the vapor with the surface and metallic spectral features upon doping with HCl.