The electrochemical reduction of polyacetylene with selected reducing agents

Abstract

The Coulombic efficiency, stability, constant-current discharge characteristics, energy density and the relation of cell potential to degree of reduction of a partly reduced polyacetylene cathode, [Na⁺ _y(CH)^y–]_x(y⩽ 0.10), in a cell of the type Na|NaPF₆(tetrahydrofuran)|[Na⁺ _y(CH)^y–]_x have been investigated. By comparison with data obtained with a (Li⁺ _y(CH)^y–]_x electrode, thermodynamic properties, such as the relation of cell potential to degree of reduction at diffusion equilibrium, appear to be intrinsic to the reduced polyacetylene and independent of the countercation, whereas kinetic properties, such as the cell potential during constant-current electrochemical reduction, vary with the countercation. The electrochemical reduction of polyacetylene with the incorporation of potassium countercations has been accomplished in a K|K ClO₄(tetrahydrofuran)|[K⁺ _y(CH)^y–]_x cell using a complexing agent to solubilize the KClO₄ in the tetrahydrofuran. A convenient electrochemical method for incorporating organic countercations into polyacetylene is discussed, together with selected properties of a [(Bu₄N)⁺ _y(CH)^y–]_x electrode.