Electrochemical Behavior of Hydrogen Peroxide at Nanocomposite of Prussian Blue with Palladium of Variable Nanogeometery Modified Electrode

Abstract

The Nanocomposite of Prussian blue (PB) with palladium of variable nanogeometery has been made as electrode modifier. Palladium of different nanogeometry, Pd1 and Pd2, as confirmed from XRD and AFM investigations is made by calcinations of palladium linked glycidoxypropyltrimethoxysilane at 500°C and 1000°C respectively. The nanostructured Pd1 and Pd2 along with gold nanoparticles of two different sizes, i.e. 50 and 20 nm (AuNP1 and AuNP2) are used for making PB nanocomposites. The chemically modified electrodes developed from these electrode modifiers are used to understand the dependence of nanogeometery on the electrochemical behavior of H2O2. Six types of chemically modified electrodes namely; (1) PB, (2) PB-AuNP1, (3) PB-AuNP2, (4) PB-Pd1, (5) PB-Pd2, and (6) PB-AuNP2-Pd2 are made for such investigation. The electrochemical observations on these modified electrode justified the following conclusions; (1) gradual improvement in redox electrochemistry of PB as well as on electrochemical behavior of H2O2 as a function of increasing nanogeometry (2) the modified electrodes made with Pd2 showed better catalytic behavior as compared to that of Pd1 toward H2O2 reduction (3) The characterization results showed that Pd2 contain PdO as major component whereas Pd1 contains Pd as major part, (4) Pd1 and Pd2 are more efficient catalyst toward H2O2 reduction as compared to that of AuNPs, irrespective of their nanosize.