Phosphomolybdate-modified multi-walled carbon nanotubes as effective mediating systems for electrocatalytic reduction of bromate

Electrocatalytic properties (towards reduction of bromate in 0.5 mol dm(-3) H2SO4) of multi-walled carbon nanotubes (CNTs) modified with phosphododecamolybdate (PMo12) monolayers have been diagnosed using cyclic voltammetry and amperometry. The ability of negatively charged PMo12-modified CNTs to attract electrostatically ultra-thin. positively charged conducting polymer (PEDOT or polypyrrole) structures is explored to grow in controlled manner hybrid organic-inorganic network electrocatalytic films. Due to the presence of three-dirnensionally distributed CNTs, the films' conductivity and porosity are improved. The hybrid systems utilizing polypyrrole, rather than PEDOT, have produced fairly higher bromate electroreduction catalytic currents. Comparison is also made to Nafion-stabilized dispersion of PMo12-modified CNTs inks. The latter system is characterized by good stability and relatively the highest sensitivities with respect to bromate concentration. (C) 2008 Elsevier B.V. All rights reserved