Electrochemical Properties of Carbon Paste Electrodes Modified with Fluorinated Materials

A carbon paste electrode (CPE) modified with polytetrafluoroethylene (PTFE) powder and perfluoropolyether (PFPE) oil was studied. These two fluorinated materials were simply mixed with graphite powder. The voltammetric behavior was compared with those of non-fluorinated materials, i.e., polyethylene (PE) powder and liquid paraffin (LP) oil. The CPE with PTFE and PFPE gave a wider polarizable potential window and a lower charging current than the non-fluorinated CPEs. When the ionic strength of the test solution was sufficiently low, the electrostatic interaction between the reactant and the fluorinated electrode surface was observed. The CPE with PTFE and PFPE was stable in a tetrahydrofuran (THF) solution, whereas other CPEs were not, due to the dissolution of the non-fluorinated materials