Leaf‐Template‐Derived Copper Oxide Nanomaterials for Nonenzymatic Electrochemical Sensing of Hydrogen Peroxide

In this study, CuO nanomaterials were prepared by an impregnation–calcination method using Dracaena fragrans leaves as a template and then modified onto the surface of a glassy carbon electrode (GCE) to construct a CuO/GCE nonenzymatic electrochemical sensor for hydrogen peroxide (H ₂ O ₂ ) detection. The structure and composition of the prepared materials were characterized by XRD, SEM, TEM, HRTEM, EDS, and X‐ray photoelectron spectroscopy. The results showed that the prepared CuO possessed a monoclinic crystal structure, a loose porous hierarchical morphology, good crystallinity, and uniform elemental distribution, which were beneficial for active‐site exposure and mass transfer. Electrochemical measurements demonstrated that CuO/GCE exhibited a remarkable electrocatalytic reduction response toward H ₂ O ₂ . Under the optimized conditions, at a working potential of −0.3 V and an electrode modification volume of 5 μL, the sensor showed a good linear response to H ₂ O ₂ in the range of 0.4–5812 μM, with a sensitivity of 0.598 μA μM ⁻¹  cm ⁻² and a detection limit of 0.25 μM. In addition, the sensor exhibited good selectivity, stability, reproducibility, and repeatability. Recovery experiments in real water samples indicated that CuO/GCE could be applied to the detection of H ₂ O ₂ in tap water and river water, showing potential for practical applications.