Synthesis, characterization of nanostructured Fe₃O₄ electrocatalysts for reduction of H₂O₂

The nanostructured Fe₃O₄ was electrodeposited on glassy carbon(GC) electrode by chronoamperometry(CA) in alkaline solutions. The prepared nanostructured Fe₃O₄ was characterized by scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results showed that the nanocrystal Fe₃O₄ was composed of nanosheets, and the thickness of nanosheets was about 10 nm. The selected area electron diffraction(SAED) patterns displayed the polycrystal Fe₃O₄. The prepared Fe₃O₄ possess enzyme mimetic activity which is similar to that of natural peroxidase. Therefore, an electrochemical sensor with the nanosheets Fe₃O₄ were fabricated to detect the reduction of H₂O₂. The sensor exhibited excellent electrochemical sensitivity with a detection limit 5 × 10^-5 mol · L^-1 (S/N=3) and the linear range was 4 × 10^-4-7 × 10^-2 mol · L^-1.