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Autori: Wrobel, D., Lukasiewicz, J., Goc, J., Waszkowiak, A., Ion, R. M
Editorial: Elsevier, Journal of Molecular Structure, 555(28), p.407-417, 2000.
Photocurrent generation in a semiconducting-metallic electrochemical cell filled with metallotetraphenyloporphyrins dissolved in polyvinylalcohol and metallotetranaphthyloporphyrins in nematic liquid crystal was investigated. The photopotential action spectra showed that the dye molecules are responsible for photoresponse. It has been shown that the intensity of photocurrent was dependent on the type of central metal complexed with the porphyrin ring of the dye molecule and also on the substituents attached to the methine bridge. The dependencies of the photopotential signal and of incident light-photosignal phase shift as a function of modulation light frequency indicate that the observed effect is due to more than one mechanism of electron transport. The results for metalloporphyrin dyes in fluid polyvinylalcohol and in nematic liquid crystal (D. Wróbel, J. Goc, R.M. Ion, J. Mol. Struct. 450 (1998) 239) were compared. The reasons of the different effectiveness of photoresponse in the electrochemical cell with different porphyrins complexed with various metals and substituted by different functional groups are discussed.
Cuvinte cheie: Electrochemical cell; Metalloporphyrin; Nematic liquid crystal; Photocurrent; Photopotential; Polyvinylalcohol