Enhanced Gas-Sensing Performances of Ru-Loaded p-Type Co<inf>3</inf>O<inf>4</inf>Nanoparticles

Abstract

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Co3O4nanoparticles (NPs) and Co3O4NPs-functionalized with 0.25, 0.50, and 1.00wt.% Ruthenium (Ru) are synthesized by the precipitation and impregnation methods. X-ray diffraction data confirm that all samples are highly crystalline with a typical cubic Co3O4NPs structure. Electron microscopic images show spherical morphologies of Co3O4nanoparticles with the diameters of 10-30nm and Ru nanoparticles with relatively small diameters of 2-4nm loaded on Co3O4surfaces. The gas-sensing results reveal that Ru loading at an optimally low Ru content of 0.25wt.% led to significantly enhanced ethanol sensing performances. Specifically, the 0.25 wt.%Ru/Co3O4sensor exhibits a good p-type response of ≈30 to 100ppm C2H5OH, short response time (0.08s), good recovery time (a few minutes) and high C2H5OH selectivity against H2S, H2, NH3, NO2, and SO2. Therefore, the Ru-loaded Co3O4sensor is a promising alternative p-type gas sensor for ethanol detection.