THE ELECTROCHEMICAL-BEHAVIOR OF METHYLENE-BLUE AT A MICROCYLINDER CARBON-FIBER ELECTRODE

The electrochemical behavior of methylene blue (MB) at a carbon fiber microcylinder electrode, was studied by cyclic voltammetry. The charge transfer coefficient cu of the electrode reaction with two-electron t ransfer is 0.5, and the number of Hf participating in the electrode pr ocess is 3 at pH 2.2-5.4, 2 at pH 5.4-6.0 and 1 at pH 6.0-10.7, respec tively. The standard electron transfer rate constant k degrees', and s tandard formal potential E degrees' of MB at various pH were determine d by using the carbon fiber microcylinder electrode. The electrode rea ction mechanism of methylene blue at various pH is proposed. The adsor bability of MB at the electrode is discussed and explored by cyclic vo ltammetry and chronocoulometric technique.