Development of NOx sensing devices based on YSZ and oxide electrode aiming for monitoring car exhausts

Abstract Recent progress in the development of zirconia-based sensing devices using zinc-family oxide electrodes for both mixed-potential and complex impedance-based types has been focused on the detection of NO x in the temperature range of 600–700 °C. The sensing characteristics of these sensors were investigated in different gaseous environments. The mixed-potential-type NO x sensor using ZnFe 2 O 4 sensing electrode (SE) have shown the highest sensitivity to NO x among other spinel-type oxides tested as SEs in the temperature range of 600–700 °C. It was also shown that the complex-impedance-based NO x sensor attached with ZnCr 2 O 4 -SE gave rather good sensing characteristics to NO x at 700 °C. Furthermore, it was discovered that the sensitivity to NO is almost equal to the sensitivity to NO 2 from 0 to 200 ppm for this sensor at 700 °C. The observed NO x sensitivity and the measured NO x concentration had almost linear correlation even in the presence of 8 vol.% H 2 O and 15 vol.% CO 2 . Based on the results obtained, we proposed laminated-type sensor structure that is the best for the present complex impedance-based NO x sensor.

[1]  Norio Miura,et al.  Stabilized zirconia-based sensor using oxide electrode for detection of NOx in high-temperature combustion-exhausts , 1996 .

[2]  Norio Miura,et al.  Impedance-based total-NOx sensor using stabilized zirconia and ZnCr2O4 sensing electrode operating at high temperature , 2002 .

[3]  Norio Miura,et al.  High-temperature NOx sensors using zirconia solid electrolyte and zinc-family oxide sensing electrode , 2002 .

[4]  Norio Miura,et al.  Impedancemetric gas sensor based on zirconia solid electrolyte and oxide sensing electrode for detecting total NOx at high temperature , 2003 .

[5]  N. Yamazoe,et al.  Stabilized zirconia-based NOx sensor using ZnFe2O4 sensing electrode , 2001 .

[6]  Norio Miura,et al.  HIGH-TEMPERATURE POTENTIOMETRIC/AMPEROMETRIC NOX SENSORS COMBINING STABILIZED ZIRCONIA WITH MIXED-METAL OXIDE ELECTRODE , 1998 .

[7]  Norio Miura,et al.  Stabilized zirconia-based sensors using WO3 electrode for detection of NO or NO2 , 2000 .

[8]  Norio Miura,et al.  Mixed potential type NO{sub x} sensor based on stabilized zirconia and oxide electrode , 1996 .

[9]  Norio Miura,et al.  Potentiometric NOx sensor based on stabilized zirconia and NiCr2O4 sensing electrode operating at high temperatures , 2001 .

[10]  Norio Miura,et al.  Mixed potential type sensor using stabilized zirconia and ZnFe2O4 sensing electrode for NOx detection at high temperature , 2002 .

[11]  Jacques Lemaire,et al.  Achieving Heavy-Duty Diesel NOx/PM Levels Below the EPA 2002 Standards--An Integrated Solution , 2000 .