Selective Carbon Monoxide-Gas-Sensing Properties over CuO/Rb<sub>2</sub>CO<sub>3</sub> Nanohybrid Structure

CuO/Rb 2 CO 3 nanohybrid structures are fabricated, and their selectivity to CO over H 2 as well as related sensing mechanisms are investigated. A series of CuO/Rb 2 CO 3 nanohybrid structures are deposited on alumina substrates by the bar-coating method. The chemical, morphological, and structural properties of the nanohybrid structures are examined by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Raman spectroscopy. The best selectivity to CO over H 2 and highest CO response level are observed upon CuO/Rb 2 CO 3 nanohybrid (5 wt.% Rb 2 CO 3 ). The gas-sensing performance of the CuO/Rb 2 CO 3 hybrid nanostructures is analyzed to prove that the catalytic properties of Rb2CO3 and its modulation ability to hole accumulation layer thickness of CuO determine the outstanding selectivity and high response level of CuO/Rb 2 CO 3 nanohybrid structure compared to pristine CuO nanoparticles.