A dual selective sensor using Au/Ce-Zr nanostructure catalytic filter to methane and ethanol in the presence of carbon monoxide
1Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
2School of Chemical Engineering, University of Tehran
SnO2 as an n-type semiconductor sensing material was prepared via a precipitation method. Ce0.8Zr0.2O2 mixed oxide supported gold nanoparticles (Au/Ce-Zr) as a nanostructure catalytic filter was synthesized by a deposition-precipitation (DP) method. BET surface area, XRD and temperature programmed reduction (TPR) techniques were employed to characterize both the filter and the sensing material. the Au/Ce-Zr catalyst activity was measured by FTIR spectrometer. Carbon monoxide and methane as indoor pollutant gases, were selected to be studied with the sensor and the filter in an integrated system. Responses of the sensor to 300 ppm of carbon monoxide and ethanol, and 10000 ppm of methane in the temperature range of 100-480°C with and without the filter. In absence of the filter layer, SnO2 sensor detect all of the gases with comparable response. While depending upon the temperatures of the filter and the sensor, selectivity for either ethanol or methane could be achieved. The operating temperatures of the sensor-filter for selective detection of ethanol and methane were 400°C and 200°C, respectively. This way with the integration of catalytic filter and the sensor a dual selective sensor is fabricated.