Preparation Method and Application of Self-Supported Bimetallic Oxide Electrode Material Derived from Prussian Blue Surface Modification

First, copper foam is ultrasonically purified and immersed in an acidic aqueous solution of potassium ferrocyanide/potassium cobalticyanide for a reaction to prepare a precursor, which is then annealed in a tube furnace to obtain copper-iron and copper-cobalt bimetallic oxide electrodes.

Free of binders, the electrodes feature excellent electrical conductivity and abundant catalytic sites: the copper-iron electrode has a sensitivity of 8536 μA·mM⁻¹·cm⁻² and a limit of detection of 0.55 μM, while the copper-cobalt electrode exhibits a sensitivity of 10398.9 μA·mM⁻¹·cm⁻² and a limit of detection of 0.34 μM. These electrodes enable accurate detection of glucose in biological fluids such as serum and saliva.