A flower-like MoS2-decorated MgFe2O4 nanocomposite: Mimicking peroxidase and colorimetric detection of H2O2 and glucose

Abstract As a member of the ferrite family, magnesium ferrite (MgFe2O4) has received attention due to its stability, catalytic and magnetic properties, and visible light activity. In this work, a MoS2@MgFe2O4 composite was obtained by dispersing as-obtained MgFe2O4 into a hydrothermal system. Both transmission electron microscopy (TEM) and scanning electron microscopy (SEM) results showed that the MoS2 had a flower-like structure, which grew on the surface of spherical popcorn-like MgFe2O4 to form a complex structure. X-ray photoelectron spectroscopy (XPS) and high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) results indicated that Mo, S, Fe, O and Mg coexisted in the MoS2@MgFe2O4 nanocomposite. The MoS2@MgFe2O4 nanocomposite showed better peroxidase mimicking activity than that of MgFe2O4 and MoS2. The peroxidase-like catalytic activity of MoS2@MgFe2O4 was affected by solution pH, temperature and 3,3,5,5-tetramethylbenzidine (TMB) concentration. Under optimal conditions, the as-obtained MoS2@MgFe2O4-based system could be used for colorimetric detection of H2O2 in the range of 2.5–300 μM. Moreover, the MoS2@MgFe2O4 based system could also be used for detection of glucose in the range of 5.0–200 μM with a detection limit of 2.0 μM. The selectivity of the colorimetric detection of glucose using MoS2@MgFe2O4 was also investigated.