Employment of Pd nanoparticles at the structure of poly aminohippuric acid as a nanocomposite for hydrogen peroxide detection

Abstract

Herein, we describe a facile and simple route to electrodeposition of poly aminohippuric acid on the surface of glassy carbon electrode (PAHA/GCE). The GC electrode consisting of PAHA was then covered with a Pd nanoparticles/metfomine functionalized multi-walled carbon nanotubes (Pd/Met-MWCNTs). The PAHA permits steady immobilization of Pd/Met-MWCNTs nanocomposite on the electrode surface to improve the stability and preserve the electrocatalytic functions of sensor. The Pd/Met-MWCNTs nanocomposite was characterized by X-ray diffraction, transmission electron microscopy, field emission scanning electron microscopy, and FT-IR spectroscopy. Electrochemical studies showed that the modified electrode exhibit excellent electro catalytic activity towards the reduction of hydrogen peroxide. Electrochemical behaviors of hydrogen peroxide at the Pd/Met-MWCNTs/PAHA/GCE were investigated by cyclic voltammetry. The effect of pH, number of cycles, potential range and scan rate on the reduction of hydrogen peroxide were investigated. The calibration graph was linear over concentration range from 0.13μM and 1000μM with respect to hydrogen peroxide with a detection limit of 0.076μM (S/N=3). The introduced modified electrode showed several advantages such as simple preparation method, high sensitivity, very low detection limits and acceptable stability. The proposed method was employed for the determination of hydrogen peroxide in rain water samples.