A. Chang, L. Miller
Jun 10, 1988
Citations
1
Influential Citations
20
Citations
Journal
Journal of Electroanalytical Chemistry
Abstract
Abstract Oligomerized 3-methoxythiophene ( 1 ) was prepared anodically. It was deposited from acetonitrile solution onto carbon electrodes. Upon oxidation at 0.4–0.6 V (SCE) in aqueous solutions of the anions salicylate or ferricyanide, the film of 1 was oxidized and incorporated the anions to maintain electroneutrality. These anion-loaded films on carbon were placed in aqueous NaCl and then the anions were released by stepping the electrode potential to pass cathodic current, e.g. to −0.4 V. In the case of salicylate, detection of the released anion by emission spectroscopy showed that at open circuit much of the salicylate exchanged out of the film over a period of 10 min, but release of the salicylate could be completed in only 30 s by stepping the potential to −0.4 V. There was a linear relationship between charge passed and amount of salicylate released. Ferricyanide release into aqueous NaCl was monitored electrochemically. Exchange of ferricyanide for chloride at open circuit was slow on the time scale of minutes, but release was completed in 30 s at −0.2 V. TCNQ was bound into 1 on carbon without electrochemical oxidation. A 1 /TCNQ charge transfer complex (solid state conductivity, σ ≈ 0.1 Ω −1 cm −1 ) is formed. This film showed electrochemical responses characteristic of both 1 and TCNQ. In aqueous NaCl formation of TCNQ XXX at −0.2 V did not give release, but the use of aqueous LiCl did. This behavior was closely analogous to that of a film of pure TCNQ, except that 1 increased the amount of active TCNQ.