MICROSTRUCTURE OF POLYFURAN PERCHLORATE-DOPED FILMS BY SCANNING AND TRANSMISSION ELECTRON MICROSCOPIES AND ELECTRON-DIFFRACTION/

Polyfuran films doped with perchlorate anions (PFu/ClO4) were studied by scanning and transmission electron microscopies and electron diffra ction in order to analyze their morphology and microstructure. Film ge neration was carried out electrochemically at constant potential, E(d) = 2.6 V (Ag/Ag+), onto platinum electrodes in acetonitrile/sodium per chlorate medium. The study of the superficial films morphology reveale d an ordered nodular structure in the films growth face, the nodular s ize depending on E(d). Alignment of nodules followed a direction paral lel to the substrate. Crystalline structures immersed in amorphous dom ains were found in planar sections and cross-sections of PFu/CLO(4) fi lms by transmission electron microscopy and selected area micro-electr on diffraction. Planar sections close to thefilm growth surface exhibi ted randomly oriented crystals, while single crystals with lamellar st ructures were detected in deeper layers. Electron diffraction patterns obtained in planar and transversal sections were consistent with a he xagonal unit cell: a = 0.68 nm and c = 0.62 nm, alpha = beta = 90 degr ees, and gamma = 120 degrees. The existence of moire patterns in plana r sections confirms the laminar structure proposed for PFu/ClO4 films.