A Flexible Graphene Paper Electrochemical Sensor With Electrodeposited Ag and Ni Nanoparticles for H₂O₂ Detection

Here, we demonstrate the detection of H2O2 with a novel freestanding flexible electrochemical sensor based on reduced graphene oxide (RGO) paper electrode decorated with silver and nickel nanoparticles (AgNiNP). Morphological and chemical characterization of the AgN-iNP/RGO was carried out using field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. Electrochemical studies revealed that this flexible paper electrode exhibited outstanding electrocatalytic activity for H2O2, which can be attributed to the cooperation and synergetic effect of AgNiNP on RGO possessing a high specific surface area. The proposed sensor showed high sensitivity in the linear range of 0.003-13 mM of H2O2 with a detection limit of 0.91 mu M. Furthermore, AgNiNP/RGO was successfully applied to determine H2O2 in real samples such as serum, milk, and hair bleaching product for practical applications. Taking into consideration the increasing need for flexible electrochemical systems, graphene-based paper (GP) sensors can provide a convenient platform for durable, flexible, selective, and sensitive sensing.