High-Linearity Hydrogen Peroxide Sensor Based on Nanoporous Gold Electrode

Fast and accurate measurement of hydrogen peroxide is essential to glucose monitoring. In this work, we describe a highly efficient H2O2 sensor through the modification of Prussian blue (PB) on the nanoporous gold film (NPG). By de-alloying from Au-Ag film, we prepare the NPG film and characterize it through SEM and AFM. Tests using chronoamperometry and cyclic voltammetry on the Prussian blue modified NPG electrodes show an excellent electrochemical performance of the sensors. Owing to the comparatively huge specific surface area in the nanoporous structure, such electrodes significantly enhance the direct electron transfer from PB nanocrystals to NPG film. Comparing to earlier PB modified electrodes, the sensor fabricated in this work exhibits the widest linearity of 0.001∼17 mM, and produces a high selectivity of 708 μA·cm−2·mM−1.