Room-temperature CO Thermoelectric Gas Sensor based on Au/Co3O4 Catalyst Tablet. (17th January 2017)

• Record Type: Journal Article
• Authors: Sun, L; Luan, W L; Wang, T C; Su, W X; Zhang, L X
• Is Part Of: Nanotechnology. Volume 28:Number 7(2017)
• Publication Date: 2017-01-17
• Subjects: CO thermoelectric gas sensor -- Au/Co3O4 catalyst tablet -- room temperature -- Co-precipitation; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/aa53f9
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: A carbon monoxide (CO) thermoelectric (TE) gas sensor was fabricated by affixing a Au/Co3 O4 catalyst tablet on a TE film layer. The Au/Co3 O4 catalyst 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 Co 3+ and water-derived species contributed to high catalytic activity. Based on the optimal Au/Co3 O4 catalyst tablet, the CO TE gas sensor worked at room temperature and showed a response voltage signal (Δ V ) 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 Δ V . The CO TE gas sensor provides a promising option for the detection of CO gas at room temperature.