In situ synthesis of Co-doped MoS2 nanosheet for enhanced mimicking peroxidase activity

Abstract

To enhance the catalytic activity of two-dimensional layered materials as versatile materials, the modification of transition metal dichalcogenide nanosheets such as MoS2 by doping with heteroatoms has drawn great interests. However, few reports are available on the study of the enzyme-like activity of doped MoS2. In this study, a facile in situ hydrothermal method for the preparation of various ultrathin transition metals (Fe, Cu, Co, Mn, and Ni) doped MoS2 nanosheets has been reported. Through the density functional theory (DFT) and steady-state kinetic analysis, the Co-doped MoS2 nanosheets exhibited the highest peroxidase-like catalytic activity among them. Furthermore, a typical colorimetric assay for H2O2 was presented based on the catalytic oxidation of colorless 3,3′,5,5′-tetramethylbenzidine (TMB) to a blue product (oxTMB) by Co-MoS2. The proposed colorimetric method showed excellent tolerance under extreme conditions and a broad linear range from 0.0005 to 25 mM for H2O2 determination. Concerning the practical application, in situ detection of H2O2 generated from SiHa cells was also fulfilled, fully confirming the great practicability of the proposed method in biosensing fields.