Silver nanodendrite modified graphene rotating disk electrode for nonenzymatic hydrogen peroxide detection

Although silver nanostructures have been widely used for H2O2 detection, the development of silver based nanomaterials with higher performance toward H2O2 detection is still needed. In this work, metallic silver nanodendrite (AgND) modified reduced graphene oxide (rGO) electrode with open pore structure was prepared by an electrodeposition method and used for H2O2 detection. The rotating disk electrode (RDE) was used to study the convective diffusion effect of H2O2 to the electrode. The performance of the AgND/rGO electrode toward H2O2 detection significantly depends on the rotation rate of the electrode. At the rotation rates of 0 and 100 rpm, the as-fabricated electrode could not detect H2O2. At higher rotation rates, wide linear ranges of detected H2O2 concentrations with a determination coefficient R2 of over 0.99 are found to be 1–100, 0.5–100, 0.1–100, and 0.05–30 mM at the electrode rotation rates of 500, 1000, 2000, and 6000 rpm, respectively. The LOD values determined at a signal-to-noise ratio of ca. 3 are about 100, 50, 30, and 10 μM at 500, 1000, 2000, and 6000 rpm, respectively. The as-fabricated electrode can detect diluted H2O2 in milk demonstrating its potential sensing application.