TY - JOUR
AU - Murray, Erica Perry
AB - The role of porosity on impedancemetric NOx sensing was investigated for sensors composed of a porous Y-stabilized ZrO2 (YSZ) electrolyte and Au wire electrodes. NOx sensors were fabricated at firing temperatures of 950°C, 1000°C, and 1050°C to establish different porous microstructures. Porosity calculations were determined from scanning electron microscopy images of the porous electrolytes using a three-dimensional statistical method. The mean porosity of sensors fired at 950°C was 50.2%, and the mean porosity value decreased to 46.7% for sensors fired at 1050°C. Impedance spectroscopy was used to measure the electrical response of the sensors while operating at 650°C, in gas atmospheres of 0–100 ppm NOx and O2 concentrations ranging from 1–18% in a balance of N2. The impedance of the sensors demonstrated a strong dependence on porosity as a decrease in porosity of about 4% resulted in nearly a 50% decrease in the impedance. Analysis of the impedance data indicted NOx sensitivity increased as the YSZ electrolyte porosity decreased. The response to NOx concentrations ≤ 10 ppm were distinguishable at operating frequencies as high as 40 Hz enabling rapid sensing.
TI - Influence of Microstructure on the Sensing Behavior of NOx Exhaust Gas Sensors
JF - Journal of the Electrochemical Society
DO - 10.1149/2.019403jes
DA - 2013-12-17
UR - https://www.deepdyve.com/lp/iop-publishing/influence-of-microstructure-on-the-sensing-behavior-of-nox-exhaust-gas-EgQncalFWe
SP - B34
EP - B38
VL - 161
IS - 3
DP - DeepDyve
ER -