Multilayer assembly of Mn-substituted Keggin-type [ZnW11O39Mn(H2O)](8-) on chemically modified glassy carbon electrode and its electrocatalytic properties

Through layer-by-layer assembly, undecatungstozincates monosubstituted by transition metals Mn, ZnW11 Mn (H2O) O-39(8-) was successfully immobilized on a glassy carbon electrode surface grafted covalently by 4-aminobenzoic acid. The electrochemical behavior of these polyoxometalates was investigated. Cyclic voltammetry proves the uniform growth of the film. They exhibit some special electrochemical properties in the films, different from those in homogeneous aqueous solution. The effect of pH on the redox behavior of ZnW11Mn(H2O)O-39(8-) in the film was discussed in detail. The multilayer film electrodes have an excellent electrocatalytic response to the reduction of H2O2 and BrO3-, and to the oxidation of ascorbic acid.