Novel Poly(pyrrole-co-3-acetyl pyrrole)-WO3 nanocomposites modified gold electrode as electrocatalytic oxidation and reduction of H2O2

Abstract

Hydrogen peroxide have strong oxidizing property hence widely used as oxidizing agent in various food production, organic compound synthesis, pulp & paper bleaching, sterilization, clinical application, pharmaceutical and environmental analysis [1-4]. H2O2 is by product of the most of the oxidative biological reactions which is most important factor of diseases like cancer, asthma, neurodegenerative disorder heart diseases [5-8] etc. Hence the detection and quantification of H2O2 was based on a simple credible, precise, fast & economical. Several methods have been developed for qualitative and quantitative detection of H2O2 such as titration [9], spectrophotometry [10], chemilumination [11], fluorometric [12] and chromatographic [13] techniques. But most of the methods have disadvantage like high cost, time consuming, and complexity while electrochemical methods have preferably low cost, high efficiency, sensitivity, selectivity [14] and reproducibility of electrode in operation. Recent studies on various polymer nanocomposites were used as electrochemical biosensor [15], drugs sensor [16,17], an environmental pollutant sensor [18], water and soil sample analysis [19], pharmaceutical and human fluids [20]. Several nanocomposites based modified electrode such as Pt Nanoparticle-Decorated rGO–CNT Nanocomposite [21], poly(azureA)-platinum nanoparticles [22], Co-embedded N-doped hierarchical carbon [23], AgAu / RGO / TiO2 nanocomposite [24], Co3O4 nanowall [25], novel metals [26-28] and conducting polymer nanocomposites [29,30] have been used for direct oxidation, reduction and detection of H2O2. In the present study chemically synthesized novel PPAP-WO3 nanocomposites (NCPs) for the electrochemical detection of H2O2 has newer approach. In the present observation we have adapted electrochemical detection of H2O2 by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV) techniques. The fabrication of an electrochemical sensor based on novel poly(pyrrole-co-3acetyl pyrrole)-WO3 nanocomposites modified gold electrode (PPAP-WO3-AuE) and its electrocatalytic oxidation and reduction of hydrogen peroxide is described here. The PPAP-WO3 nanocomposites were synthesized by chemical method and characterized by different techniques. The WO3 nanoparticles incorporated with PPAP were confirmed by x-ray diffraction pattern, scanning electron microscopy and transmission electron microscope micrograph. The electrochemical behaviour of PPAP-WO3-AuE towards the electro catalytic oxidation and reduction of hydrogen peroxide was investigated by cyclic voltammetry, differential pulse voltammetry and square wave voltammetry. The observed DPVs and SWVs response depend linearly on concentration of hydrogen peroxide in the range of 1-10 mM and with limit of detection (LOD) is 1×10 M. The correlation coefficients were found as 0.991, 0.930 and sensitivity observed was 47.64 A/mM.cm and 8.31A/mM.cm. These results indicate the PPAP-WO3-AuE exhibited good platform and could be used for electrochemical determination of hydrogen peroxide.