Nano-silver/multi-walled carbon nanotube composite films for hydrogen peroxide electroanalysis

A modified electrode has been fabricated with nano-silver/multi-walled carbon nanotube composites and characterized with scanning electron microscopy, X-ray powder diffraction and cyclic voltammetry. The electrochemical characteristics of the modified electrode have been studied. It has been found that the modified electrode can be used for the direct electroanalysis of hydrogen peroxide. A wave appeared at -0.64 V (vs. SCE) on the modified electrode due to the reduction of hydrogen peroxide. There was a linear relationship between hydrogen peroxide concentration and the cathodic differential pulse voltammetric current in the range 0.35-15 mM with a detection limit of 0.2 mM (S/N = 3). A medical hydrogen peroxide disinfection liquid was analyzed and recoveries were obtained between 97.5 and 103.8%.