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 (Cu 3 N NA/CF) as a dual‐functional catalyst electrode for efficient glucose oxidation in alkaline solutions and hydrogen peroxide (H 2 O 2 ) reduction in neutral solutions. Electrochemical tests indicate that such Cu 3 N NA/CF possesses superior non‐enzymatic sensing ability toward rapid glucose and H 2 O 2 detection with high selectivity. At 0.40 V, this sensor offers a high sensitivity of 14 180 μA m m cm −2 for glucose detection, with a wide linear range from 1 μ m to 2 m m , a low detection limit of 13 n m ( S / N =3), and satisfactory stability and reproducibility. Its application in determining glucose in human blood serum is also demonstrated. Amperometric H 2 O 2 sensing can also been realized with a sensitivity of 7600 μA m m cm −2 , a linear range from 0.1 μ m to 10 m m , and a detection limit of 8.9 n m ( S / N =3). This 3D‐nanoarray architecture holds great promise as an attractive sensing platform toward electrochemical small molecules detection.