ZnFe₂O₄/Graphitic Carbon Nitride\nNano/Microcomposites for the Enhanced Electrochemical Sensing of H₂O₂

Abstract

Hydrogen peroxide (H₂O₂) sensors\nwith high\nsensitivity and stable detecting ability have been particularly in\ndemand in the charming medical health and environmental monitoring.\nIn this work, spherical ZnFe₂O₄/g-C₃N₄ (ZFO/g-C₃N₄) nano/microcomposites\nwith different contents of g-C₃N₄ were controllably\nsynthesized through a solvothermal calcination strategy, and the morphologies\nof their target materials were systematically characterized via scanning\nelectron microscopy, energy dispersive spectroscopy, high-resolution\ntransmission electron microscopy, Fourier transform infrared spectroscopy,\nand X-ray diffraction. Subsequently, the as-prepared spherical ZFO/g-C₃N₄ composites are designed as an outstanding electrochemical\nsensor for H₂O₂, and its sensitivity was evaluated\nusing cyclic voltammetry and chronoamperometry techniques. The ZFO/g-C₃N₄ microspheres exhibited a synergistic catalytic\neffect with a broad linear detection range between 5 and 200 μM\nand a detection limit of 1 μM (S/N = 3). The enhanced electrochemical\nperformances of uniform ZFO/g-C₃N₄ composites\nwith a three-dimensional net structure proved that the combination\nof a two-dimensional material (C₃N₄) and spinel-type\nmetal oxide (ZnFe₂O₄) produces apparent activity,\nshowing broad application potential in nonenzymatic sensors.