Petal-shaped MoS₂/FeS₂@C nanocomposites with enhanced peroxidase-like activity for colorimetric detection of H₂O₂ and glutathione

In this work, we reported the FeS₂@C nanocapsules-modified petal-shaped MoS₂ nanosheets (MoS₂/FeS₂@C) peroxidase prepared by arc discharging combined with hydrothermal methods. We thoroughly investigated their peroxidase-like activities in the colorimetric detection of H₂O₂ and glutathione (GSH). The results indicate that the prepared petal-shaped MoS₂/FeS₂@C nanocomposites exhibit enhanced peroxidase activity compared to the single-component MoS₂ or FeS₂@C. The detection ranges and detection limits (LOD) are 1–150 μM and 0.43 μM for H₂O₂, respectively, while for GSH, they are 0.2–40 μM and 0.14 μM, respectively. The superior peroxidase-like activity of the MoS₂/FeS₂@C results from the synergy between the MoS₂ and FeS₂@C. This synergy creates abundant active sites and more substance shuttle channels, which increases the cyclic efficiency among Fe³⁺/Fe²⁺ and Mo⁶⁺/Mo⁴⁺ and improves the yield of hydroxyl radicals. As a result, the MoS₂/FeS₂@C nanocomposites acquired quick electron transport and improved peroxidase-like catalytic performance. Moreover, the MoS₂/FeS₂@C nanocomposites exhibit high stability and selectivity, retaining high-activity levels even after 30 days. These make them promising candidates for use in biosensing and catalysis applications.