Facile and controllable synthesis of Prussian blue nanocubes on TiO2–graphene composite nanosheets for nonenzymatic detection of hydrogen peroxide

Abstract

A novel nonenzymatic sensor for hydrogen peroxide (H₂O₂) is developed based on a Nafion/Prussian blue/TiO₂–graphene nanocomposite (Nafion/PB/TiO₂–GR). The PB/TiO₂–GR composite was prepared by the electrodeposition of PB nanocubes on the surface of TiO₂–GR composite nanosheets and Nafion was used as a stabilizer. The Nafion/PB/TiO₂–GR composite modified glassy carbon electrode (Nafion/PB/TiO₂–GR/GCE) shows good electrocatalytic activity in the reduction of H₂O₂ and is used as an amperometric sensor. The sensor exhibits a linear response for H₂O₂ over concentrations ranging from 40 nM to 2 mM with a high sensitivity of 480.97 μA mM⁻¹ cm⁻² and a low detection limit (S/N = 3) of 8.6 nM. Additionally, the sensor exhibits long-term stability, good reproducibility and anti-interference. This study provides a new kind of nanocomposite modified electrode for electrochemical sensors.