Prussian Blue electrodeposited on MWNTs–PANI hybrid composites for H2O2 detection

A Prussian Blue (PB)/polyaniline (PANI)/multi-walled carbon nanotubes (MWNTs) composite film was fabricated by step-by-step electrodeposition on glassy carbon electrode (GCE). The electrode prepared exhibits enhanced electrocatalytic behavior and good stability for detection of H2O2 at an applied potential of 0.0 V. The effects of MWNTs thickness, electrodeposition time of PANI and rotating rate on the current response of the composite modified electrode toward H2O2 were optimized to obtain the maximal sensitivity. A linear range from 8 × 10−9 to 5 × 10−6 M for H2O2 detection has been observed at the PB/PANI/MWNTs modified GCE with a correlation coefficient of 0.997. The detection limit is 5 × 10−9 M on signal-to-noise ratio of 3. To the best of our knowledge, this is the lowest detection limit for H2O2 detection. The electrode also shows high sensitivity (526.43 μA μM−1 cm−2) for H2O2 detection which is more than three orders of magnitude higher than the reported.