The electrocatalytic reduction of hydrogen peroxide based on coulombically linked ferrocene at L-cysteine self-assembled monolayers

A composite film containing ferrocene has been fabricated on L-Cysteine self-assembled monolayers film modified gold electrode by electrostatic adsorption. Attenuated total reflection-fourier transform infrared, scanning electron microscopy, cyclic voltarnmetry and chronocoulometry were used to determine the electrochemical properties of the composite film. One reversible redox couple was observed in the pH range of 5.1-9.5, which was attributed to a one-electron electrochemical process of Fc with diffusion coefficient 1.01 x 10(-7) cm(2)/s. Moreover, the composite film showed good catalytic activity for the reduction of H2O2. The catalytic current of H2O2 vs. its concentration had a good linearity in the range of 4.0 x 10(-7) - 3.5 x 10(-5) mol/L, with the correlation coefficient of 0.9986 (differential pulse voltammetry) and the detection limit of 8.0 x 10(-8) mol/L.