Preparation of <TEX>$SnO_2$</TEX> Semiconducting Gas Sensor by Wet Process

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J. Korean Ceram. Soc. > Volume 23(3); 1986 > Article

Journal of the Korean Ceramic Society 1986;23(3): 53.

습식방법에 의한 $SnO_2$ 반도체 가스센사 제조

전병식, 김홍대¹, 최병현², 최성근²

국립공업 시험원
¹도자기시험소
²도자기 시험소

Preparation of $SnO_2$ Semiconducting Gas Sensor by Wet Process

ABSTRACT

A gas sensor which has been made by wet process had fabricated by coating each of the mixture on alumina tube and firing at 85$0^{circ}C$ for 3hrs. A gas concentration such $H_2$, CO, $C_3H_8$, $C_2H_2$ and $CH_4$ vs its detection voltage characteristics has been in-vestigated on $SnO_2-In_2O_3-MgO$ system doped with PdO, $La_2O_3$, $ThO_2$, NiO and $Nb_2O_5$ The optimum sensitivity composition for various gases were 90w/o $SnO_2$-9w/o $In_2O_3$-1w/o MgO for $H_2$, $C_2H_2$ CO and $C_3H_8$ and 95w/o $SnO_2$-4w/o $In_2O_3$-1w/o MgO for $CH_4$. The sample which has been made by wet process than dry process had predominated sensitivity for each gases and particle size of the sample coprecipitated with PH=9 was 0.1${mu}{textrm}{m}$ The $SnO_2$-In2_O_3-MgO$ system doped with 2w/o $Nb_2O_5$ and NiO was the most sensitive for $H_2$ and $C_2H_2$ gas. In $SnO_2$-In2_O_3-MgO$ system doped with $ThO_2$ the sensitivity of $H_2$ gas was decreased but CO gas was in-creased when dopant con was increased.