Characterization of Polyacetylene and Polyacetylene Doped with Palladium
نویسندگان
چکیده
Samples of Naarmann polyacetylene, denoted as N-(CH)x, (unstretched) and polyacetylene doped with Pd have been investigated, being characterized by: (i) conductivity using the four-point method, (ii) bulk concentration of Pd using the atomic absorption method, (iii) bulk density using helium pycnometry, (iv) surface composition by X-ray photoelectron spectroscopy and (v) electron transport parameter, such as the inelastic mean free path, using elastic peak electron spectroscopy. For evaluating the inelastic mean free path, a Ni standard has been applied, using three spectrometers in the electron energy range 200–5000 eV. The experimental values of the inelastic mean free path have been compared with that obtained earlier by Tanuma et al. for Shirakawa polyacetylene and with that resulting from the TPP-2M predictive equation and the G1 predictive formula of Gries. The scatter between the experimental and theoretical inelastic mean free path values has been discussed. The experimental inelastic mean free path values depend on the density of the polymers and the surface composition, associated with the contamination from the reaction synthesis.
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