Chronoamperometric Determination of H2O2 with the Modified Electrode of Nano Pt/MWCNT′s-CTS/GCE

One mg of multi-wall carbon nano-tubes (MWCNT′s) was dispersed in 5 g·L-1 chitosan solution, and the dispersion was dropped on the surface of glassy carbon electrode (GCE), which was then electrodeposited in H2［PtCl6］ (1+99) solution at -0.2 V for 90 s to have it filmed with platinum nanoparticles on its surface. The modified electrode thus prepared was named abbreviately as nano Pt/MWCNT′s-CTS/GCE. The microstructure of the surface of the modified electrode was characterized by SEM and its electrochemical property was studied by cyclic voltammetry and chronoamperometry. It was found that the modified electrode exhibited excellent electrocatalytic responses towards the reduction of H2O2. Linear relationship between values of reduction peak current and concentration of H2O2 was obtained in the range from 6.30×10-7 to 1.52×10-3mol·L-1, with detection limit (3S/N) of 2.13×10-7mol·L-1. Precision of the method was tested at the concentration level of 0.35 mmol·L-1 H2O2 standard solution for 8 determinations giving value of RSD (n=8) of 0.27%.