Gas Sensing Characteristics of Catalyst-added <TEX>$In_2O_3$</TEX> Thick Film for Detecting <TEX>$NO_x$</TEX> of High Concentration

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J. Korean Ceram. Soc. > Volume 36(12); 1999 > Article

Journal of the Korean Ceramic Society 1999;36(12): 1322.

고농도 $NO_x$ 감지용 $In_2O_3$ 후막가스센서의 Al, Ru 및 $SnO_2$ 첨가에 의한 특성 향상

박종현, 김동현, 이종영¹, 김광호

부산대학교 무기재료공학과
¹부산대학교 생산기술연구소 특별연구원

Gas Sensing Characteristics of Catalyst-added $In_2O_3$ Thick Film for Detecting $NO_x$ of High Concentration

ABSTRACT

In2O3 thick film gas sensor for detecting NOx gas of high concentration was fabricated by a screen printing technique. This work focussed on investigation of the change of sensitivity to NOx gas with firing temperatures of sensing layer and on improvement of the sensitivity by adding catalysts such as Al,. Ru, and SnO2 The cross sensitivites of sensor to CO, H2, CH4 and i-C4H10 gases were also examined under NO2 gas concentration of 200ppm Pure In2O3 gas sensor prepared at a firing temperature of 50$0^{circ}C$ showed a maximum sensitivity to NOx gas at the operating temperature of 40$0^{circ}C$ Al(0.004 wt%)-In2O3 sensor largely improved the sensitivities to both NO2 and NO gas and showed a superior selectivity compared with other gas sensors.

Key words: NOx gas sensor, $In_2O_3$ thick film, Catalyst, Cross sensitivity