FeS2-doped MoS2 nanoflower with the dominant 1T-MoS2 phase for enhanced peroxidase activity

Nanozymes with peroxidase activity have lower catalytic activity compared to natural enzymes. Therefore, it is of great significance to develop and design artificial enzymes with high catalytic activity. FeS2-doped MoS2 (FeS2-MoS2) nanoflower is synthesized via a hydrothermal method, using Anderson-type polyoxometalates (FeMo6) as precursors. The X-ray photoelectron spectroscopy (XPS) and Raman spectrum of FeS2-MoS2 confirm the presence of the 1T-MoS2 phase. FeS2-MoS2 with different 1T/2H-MoS2 phase ratios are synthesized by controlling the reaction time. As a nanozyme, the obtained FeS2-MoS2 can promote the oxidation of 3,3 ',5,5 '- tetramethylbenzidine (TMB) to oxTMB, showing peroxidase activity. FeS2-MoS2 at a reaction time of 12 h exhibits higher peroxidase activity compared to samples prepared at other reaction times. The catalytic activity of FeS2-MoS2 is 3 times that of MoS2. The Km value for H2O2 was 110 times that of horseradish peroxidase (HRP), indicating that the FeS2-MoS2 had a better affinity for H2O2. The excellent catalytic activity may be due to the synergistic effect of bimetal, larger specific surface area, the high content of 1T-MoS2 (77.52 %) and defect. As far as we know, the FeS2-MoS2 nanoflower exhibits an exceptionally low detection limit of 0.52 mu M for the colorimetric sensing of H2O2. This research presents a novel approach for creating high-performing nanozyme catalysts.