Low-potential sensitive hydrogen peroxide detection based on nanotubular TiO2 and platinum composite electrode

In this work, a novel sensor for detecting hydrogen peroxide was constructed on the base of nanotubular TiO2 and platinum nanoparticles. The morphology, structural, and electrochemical properties of the Pt/TiO2 nanocomposite electrodes were characterized by SEM, XRD and electrochemical methods. With an operating potential of +0.3 V versus Ag/AgCl, the sensor produces catalytic oxidation currents at the nanocomposite electrode, which can be exploited for quantitative determinations. ne amperometric signals are linearly proportional to hydrogen peroxide concentration in the range 4 x 10(-6) to.1.25 x 10(-3) M. The regression equation is I (mu A) = 0.85 c (mM) + 0.16 with a correction coefficient of 0.997. At a signal-to-noise ratio of 3, a detection limit of 4.0 mu M H2O2 can be observed for the nanocomposite electrode. In addition, the sensor has a good stability and reproducibility. The construction process is simple and inexpensive. The results demonstrated that nanotubular TiO2 exhibits great prospect for developing a class of ideal and novel bioreactors and biosensors.