Abstract: The novel multilayer nano-composite films consisting of vanadium mono-substituted polyoxometalates (PMo11VO4-40) and a generation-4 poly(amidoamine) (PAMAM) dendrimer were fabricated on quartz and glassy carbon electrode substrates by layer-by-layer self-assembly technique. The incorporation of PMo11VO4-40 and PAMAM into the films was confirmed by XPS. The multilayer films were grew gradually and uniformly in the synthesis process as monitored by UV-Vis and cyclic voltammetry. Four pairs of redox peaks which corresponded to V5+/V4+ and Mo6+/Mo5+ were observed in the cyclic voltammogram of multilayer films. The dependence of peak current on scan rate was indicative of redox surface-confined species and the charge transfer was very quick. The formal potential of the composite films was shifted linearly to negative position at higher pH, which implied that the protons were involved in the redox processes of polyoxometalates. The multilayer films were stable and exhibited good catalytic activities for the reduction of NO-2 , BrO-3, and H2O2.

Key words: Polyoxometalate, Poly(amidoamine), Multilayer films, Electrocatalysis