A novel nonenzymatic hydrogen peroxide sensor based on reduced graphene oxide/ZnO composite modified electrode

A novel nonenzymatic, amperometric sensor for hydrogen peroxide (H ₂O ₂) was developed based on an electrochemically prepared reduced graphene oxide (RGO)/zinc oxide (ZnO) composite using a simple and cost effective approach. RGO/ZnO composite was fabricated on a glassy carbon electrode (GCE) by a green route based on simultaneous electrodeposition of ZnO and electrochemical reduction of graphene oxide (GO). The morphology of the as-prepared RGO/ZnO composite was investigated by scanning electron microscopy (SEM). Attenuated total reflectance (ATR) spectroscopy has also been performed to confirm the ample reduction of oxygen functionalities located at graphene oxide (GO). The electrochemical performance of the RGO/ZnO composite modified GCE was studied by amperometric technique, and the resulting electrode displays excellent performance towards hydrogen peroxide (H ₂O ₂) at -0.38 V in the linear response range from 0.02 to 22.48 μM, with a correlation coefficient of 0.9951 and short response time (<5 s). The proposed sensor also has good operational and storage stability with appreciable anti-interferring ability.