Copper‐Nitride Nanowires Array: An Efficient Dual‐Functional Catalyst Electrode for Sensitive and Selective Non‐Enzymatic Glucose and Hydrogen Peroxide Sensing

It is highly attractive to develop non-noble-metal nanoarray architecture as a 3D-catalyst electrode for molecular detection due to its large specific surface area and easy accessibility to target molecules. Here, we report the development of a copper-nitride nanowires array on copper foam (Cu₃ N NA/CF) as a dual-functional catalyst electrode for efficient glucose oxidation in alkaline solutions and hydrogen peroxide (H₂ O₂ ) reduction in neutral solutions. Electrochemical tests indicate that such Cu₃ N NA/CF possesses superior non-enzymatic sensing ability toward rapid glucose and H₂ O₂ detection with high selectivity. At 0.40 V, this sensor offers a high sensitivity of 14 180 μA mm cm^-2 for glucose detection, with a wide linear range from 1 μm to 2 mm, a low detection limit of 13 nm (S/N=3), and satisfactory stability and reproducibility. Its application in determining glucose in human blood serum is also demonstrated. Amperometric H₂ O₂ sensing can also been realized with a sensitivity of 7600 μA mm cm^-2 , a linear range from 0.1 μm to 10 mm, and a detection limit of 8.9 nm (S/N=3). This 3D-nanoarray architecture holds great promise as an attractive sensing platform toward electrochemical small molecules detection.