Freestanding Films of Reduced Graphene Oxide Fully Decorated with Prussian Blue Nanoparticles for Hydrogen Peroxide Sensing

Abstract

Developing thin, freestanding electrodes that work simultaneously as a current collector and electroactive material is pivotal to integrating portable and wearable chemical sensors. Herein, we have synthesized graphene/Prussian blue (PB) electrodes for hydrogen peroxide detection (H 2 O 2 ) using a twostep method. First, an reduced graphene oxide/PAni/Fe 2 O 3 freestanding film is prepared using a doctor blade technique, followed by the electrochemical deposition of PB nanoparticles over the films. The iron oxide nanoparticles work as the iron source for the heterogeneous electrochemical deposition of the nanoparticles in a ferricyanide solution. The size of the PB cubes electrodeposited over the graphene-based electrodes was controlled by the number of voltammetric cycles. For H 2 O 2 sensing, the PB10 electrode achieved the lowest detection and quantification limits, 2.00 and 7.00 μM, respectively. The findings herein evidence the balance between the structure of the graphene/PB-based electrodes with the electrochemical performance for H 2 O 2 detection and pave the path for developing new freestanding electrodes for chemical sensors.