Preparation of Manganese Dioxide Nanozyme as Catalyst for Electrochemical Sensing of Hydrogen Peroxide

摘要

The two-dimensional manganese dioxide nanoflakes (MnO2 NFs) with peroxidase-like activity was synthesized by a biomineralization method using bovine serum albumin (BSA) as a template. After then MnO2 NFs was hybridized with reduced graphene oxide (rGO) for electrochemical sensing of hydrogen peroxide (H2O2). The composition and structure of MnO2 NFs were characterized by Energy Dispersive X-ray Spectrometer (EDX) and Transmission Electron Microscope (TEM), and the morphology of hybridized material were characterized by Scanning Electron Microscopy (SEM). Electrochemical experiments showed that the hybridized material exhibited good sensing performance toward the reduction of H2O2 with broad linear ranges of 20 nM to 5 μM and 5μM to 800 μM. The limit of detection is 14.92 nM (S/N=3). The good sensing performance is ascribed to the synergistic effects of the special morphology of MnO2 NFs and good conductivity of the reduced graphene oxide (rGO). The proposed sensor can be used for monitoring the H2O2 content in real biological environments with good stability, repeatability and selectivity.