Electropolymerization of pyrrole on a tantalum electrode

Electropolymerization of pyrrole was carried out on tantalum as a base metal electrode. The Ta electrode retards polymerization at lower pyrrole concentrations because of the formation of insulating Ta₂O₅. However, at high concentrations of pyrrole, the polymerization proceeds efficiently to yield a polypyrrole (PPy) film, similar to that on a Pt electrode. The PPy film on a Ta electrode shows the same electroactivity and electric conductivity as that on a Pt electrode. Electropolymerization on Ta is accompanied by a decrease in electrode area due to the formation of the Ta₂O₅, the behavior of which is the only difference from that on Pt.