A novel field ionization gas sensor based on self-organized CuO nanowire arrays

• A novel field ionization gas sensor has been fabricated for the first time based on self-organized arrays of CuO nanowires.
• Nanoscale size of CuO tips make it possible to have gas ionization sensor works at less than 100 V.
• The metal oxide nature of CuO nanowires caused controlled breakdown current of gas ionization sensor which results in good stability.

In this study, we present fabrication and characterization of a gas ionization sensor based on high aspect ratio one-dimensional CuO nanowires as the field enhancing medium. Self-organized arrays of CuO nanowires have been synthesized based on a low-cost thermal oxidation method and integrated into a gas ionization sensor (GIS). The self-organized arrays of CuO nanowires have been employed to detect the identity of several gas species such as He, Ar and CO at ambient temperature and pressure. The sharp nanoscale size of CuO tips provide very high electric fields at moderate voltages (less than 100 V) and provoke the breakdown of different gases. The reduced breakdown current of the metal oxide CuO nanowire electrodes result in reduced structural deformation. The proposed GIS based on CuO nano-tips exhibits good repeatability and selectivity for various types of gases and their mixtures.