Peroxidase‐Like Layered Double Hydroxide Nanoflakes for Electrocatalytic Reduction of H2O2

Abstract

AbstractPeroxidase‐like layered double hydroxide (LDH) nanoflakes were synthesized directly and facilely by a one‐pot chemical method, hydrothermal treatment. The as‐prepared LDHs were characterized by transmission electron microscopy, scanning electron microscopy, X‐ray diffraction, Fourier transform IR, and cyclic voltammetry. The functionalized LDHs immobilized on the glassy carbon electrode exhibited a well‐defined pair of redox peaks, excellent electrocatalytic activity toward the reduction of hydrogen peroxide without inhibition of dissolved oxygen and a higher affinity for H2O2, just like the peroxidase. The low apparent Michaelis–Menten constant was only 242 μM. The electrochemical response to H2O2 shows a linear range of 12–254 μM with the calculated detection limit of 2.3 μM at a signal‐to‐noise ratio of 3. Furthermore, compared with most metal hexacyanoferrates, the peroxidase‐like LDHs are very stable in neutral and alkaline solution. The electrochemical and electrocatalytic behavior of the functionalized LDHs indicate that they may be useful to explore man‐made mimics of enzyme in electrochemical biosensors.