Electrochemical synthesis of Fe3O4-PB nanoparticles with core-shell structure and its electrocatalytic reduction toward H2O2

The Fe 3 O 4 -Prussian blue (PB) nanoparticles with core-shell structure have been in situ prepared directly on a nano-Fe 3 O 4 -modified glassy carbon electrode by cyclic voltammetry (CV). First, the magnetic nano-Fe 3 O 4 particles were synthesized and characterized by X-ray diffraction. Then, the properties of the Fe 3 O 4 -PB nanoparticles were characterized by CV, electrochemical impedance spectroscopy, and superconducting quantum interference device. The resulting core-shell Fe 3 O 4 -PB-modified electrode displays a dramatic electrocatalytic ability toward H 2 O 2 reduction, and the catalytic current was a linear function with the concentration of H 2 O 2 in the range of 1 × 10 −7 ~5 × 10 −4 mol/l. A detection limit of 2 × 10 −8 ( s / n = 3) was determined. Moreover, it showed good reproducibility, enhanced long-term stability, and potential applications in fields of magnetite biosensors.