Development and Characterization of Highly Efficient Integrated Electrocatalytic Systems utilizing Nanostructured Catalysts and Gold Nanoparticles

摘要

In the present work we explore the phosphododecamolybdate heteropolyblue-mediated synthesis of gold nanoparticles, acting as a new generation electrocatalytic system exhibiting appreciable activity toward reduction of carbon oxide (Ⅳ) and reduction of oxygen (after combining with Co-porphyrin). We explore the ability of highly-concentrated Keggin-type phosphomolybdates to attach within the plain gold surfaces to achieve the highly shape-selective synthesis of approximately spherical or anisotropic Au nanostructures of controlled sizes. The tunable concentrations of reducing (and stabilizing) agent H_3[H_4P(Mo~Ⅴ)_4(Mo~Ⅵ)_8O_(40)] allowed us to produce a wide range of nanostructured gold with specific sizes and shapes. The aim of this work was to study the applicability of phosphomolybdate-protected gold nanoparticles to create microporous matrix for reduction of carbon dioxide and the active support for the Co-porphyrin catalytic centers towards reduction of oxygen. Keggin-type structures-stabilizing gold nanoparticles were expected to provide electrons and mobile protons to the vicinity of Co-porphyrin, while gold nanoparticles were responsible for high electronic conductivity combined with electrocatalytic activity towards CO_2 and H_2O_2 reduction. The hybrid catalyst based on Co-porphyrin and phosphomolybdate-protected gold nanoparticles led to synergistic effect that was evident from some positive shift of the oxygen reduction voltammetric potentials and significant increase of the voltammetric currents in all case.