title: Room-temperature CO Thermoelectric Gas Sensor based on Au/Co3O4Catalyst Tablet.
abstract: A carbon monoxide (CO) thermoelectric (TE) gas sensor was fabricated by affixing a Au/Co3O4catalyst tablet on a TE film layer. The Au/Co3O4catalyst tablet was prepared by a co-precipitation and tablet compression method and its possible catalytic mechanism was discussed by means of x-ray diffraction, field emission scanning electron microscopy, high resolution transmission electron microscopy, x-ray photoelectron spectroscopy, temperature-programmed reduction of hydrogen, Fourier transform infrared spectroscopy and Brunauer-Emmett-Teller analysis. The optimal catalyst, with a Au content of 10 wt%, was obtained at a calcination temperature between 200 and 300 °C. The small size of the Au nanoparticles, high specific surface, the existence of Co3+and water-derived species contributed to  high catalytic activity. Based on the optimal Au/Co3O4catalyst tablet, the CO TE gas sensor worked at room temperature and showed a response voltage signal (ΔV) of 23 mV, high selectivity among hydrogen and methane, high stability, and a fast response time of 106 s for 30 000 ppm CO/air. In addition, a CO concentration in the range of 5000-30 000 ppm could obviously be detected and exhibited a linear relationship with ΔV. The CO TE gas sensor provides a promising option for the detection of CO gas at room temperature.
authors.affiliation: School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, People's Republic of China.
authors.forename: L
authors.initials: L
authors.lastname: Sun
authors.forename: W L
authors.initials: WL
authors.lastname: Luan
authors.forename: T C
authors.initials: TC
authors.lastname: Wang
authors.forename: W X
authors.initials: WX
authors.lastname: Su
authors.forename: L X
authors.initials: LX
authors.lastname: Zhang