THE EFFECT OF ADDITIVES IN TIN OXIDE ON THE SENSITIVITY AND SELECTIVITY TO NOX AND CO

被引：74

作者：

SAYAGO, I ^{[1
]}

GUTIERREZ, J ^{[1
]}

ARES, L ^{[1
]}

ROBLA, JI ^{[1
]}

HORRILLO, MC ^{[1
]}

GETINO, J ^{[1
]}

RINO, J ^{[1
]}

AGAPITO, JA ^{[1
]}

机构：

[1] UNIV COMPLUTENSE MADRID,FAC CIENCIAS FIS,DEPT ELECTR,E-28040 MADRID,SPAIN

来源：

SENSORS AND ACTUATORS B-CHEMICAL | 1995年 / 26卷 / 1-3期

关键词：

DOPING; TIN OXIDE; GAS SENSORS;

D O I：

10.1016/0925-4005(94)01548-V

中图分类号：

O65 [分析化学];

学科分类号：

070302 ; 081704 ;

摘要：

Undoped and Pt-, In- and Al-doped SnO2 film gas sensors prepared by reactive sputtering (r.f.) were tested for detection of NOx and CO, and their sensitivities were studied in dry synthetic air. The concentrations of CO vary from 50 to 1000 ppm and that of NO, from 2 to 70 ppm. The selectivity of the sensors was studied to determine the response of NO, when CO was the interfering gas. The sensitivity to gases was studied in the temperature range from 300 to 675 K in order to find the optimum detection temperature. The experiments to determine the interference effects of CO on the response to NOx were carried out at 525 K. Measurements of electrical conductance show that these films have a sensitivity higher than 1000% to NOx at temperatures below 575 K and 50 ppm gas concentration. At the same temperatures the sensitivities to CO at 1000 ppm always remain lower than 100%. The best sensitivity to NOx is achieved with sensors doped with Al or In and operated in the range 300-525 K. CO detection begins at 325 K, the best sensitivity being obtained with sensors doped with Pt. We observe that sensitivity, selectivity, optimum work temperature and response time depend on the dopants.

引用

页码：19 / 23

页数：5

共 8 条

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