Synthesis and CO Gas-Sensing Properties of CuO and Spinel Ferrite Nanocomposite Thin Films

A nanocomposite thin film composed of tenorite (CuO) and spinel ferrite (CuxFe3−xO45 has been prepared by radio-frequency sputtering method followed by a post-deposition thermal annealing. The nanostructure was examined by grazing X-ray diffraction, atomic force microscopy and scanning electron microscopy. CuO-CuxFe3−xO4 nanocomposite layer was deposited on the top of screenprinted gold electrodes onto SiO2(200 nm)/Si substrate. It was found that this material contains p–n nano-heterojunctions, was sensitive to 500 ppm carbon monoxide at the operational temperature of 400 °C and exhibited a large response of 90%