Growth and sensing properties of networked p-CuO nanowires

Networked p-CuO nanowires were grown on patterned-electrode pads by the thermal oxidation of Cu layers. Vertically aligned CuO nanowires grown on adjacent round-shape electrode pads were entangled, eventually forming nanowire-nanowire junctions. The sensing properties of the networked CuO nanowires were examined for a range of oxidizing gases, such as NO₂, SO₂ and O₂, and reducing gases, such as CO, C₆H₆, C₇H₈, and H₂, and compared with those of networked n-SnO₂ nanowires. The gas responses of the networked CuO nanowires to the tested oxidizing gases were inferior to those of networked n-SnO₂ nanowires. In contrast, for reducing gases, the networked CuO nanowires showed comparable gas responses to the networked n-SnO₂ nanowires. The results suggest that the networked CuO nanowires are more promising for the detection of reducing gases rather than oxidizing gases.