An unusual H2O2 electrochemical sensor based on Ni(OH)2 nanoplates grown on Cu substrate

In this work, Ni(OH)2 nanoplates grown on the Cu substrate were synthesized and characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Then a novel Cu–Ni(OH)2 modified glass carbon electrode (Cu–Ni(OH)2/GCE) was fabricated and evaluated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and typical amperometric response (i–t) method. Exhilaratingly, the Cu–Ni(OH)2/GCE shows significant electrocatalytic activity toward the reduction of H2O2. At an applied potential of −0.1 V, the sensor produces an ultrahigh sensitivity of 408.1 μA mM−1 with a low detection limit of 1.5 μM (S/N = 3). The response time of the proposed electrode was less than 5 s. What's more, the proposed sensor displays excellent selectivity, good stability, and satisfying repeatability.