Detection of glucose using a thin-walled honeycombed MnO2 grown on mesoporous CoFe2O4 nanosheets

Abstract

We prepared a novel composite material CoFe2O4 @MnO2 by dealloying Al91Co3Fe6 ribbons followed by a calcination step and a hydrothermal reaction. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to analyze the phase constitutions, microstructures, and morphology. Results show that thin-walled honeycombed MnO2 growth on mesoporous CoFe2O4 nanosheets is the key to synthetize CoFe2O4 @MnO2. A three-electrode system was used for the electrochemical sensing of glucose. The sensitivity of the composite material when used as glucose detection electrode was of 1362.83 μA·mM−1·cm−2, significantly higher than that of CoFe2O4 (590.37 μA·mM−1·cm−2) and MnO2 (248.95 μA·mM−1·cm−2). Additionally, CoFe2O4 @MnO2 exhibits remarkable long-term stability and an impressive low detection limit of 1.32 μM. Our results conclude that its larger specific area and high abundance of charge transport channels contribute to its excellent properties. Additionally, the presence of a large number of metallic-oxygen bonds significantly improves its electro-catalytic properties for the detection of glucose.