Sensing Performance of a YSZ-Based Electrochemical NO₂ Sensor Using Nanocomposite Electrodes

Abstract

An electrochemical NO 2 sensor is fabricated using yttria-stabilized zirconia as electrolyte and SnO 2 -NiO nanocomposites as sensing electrodes. The SnO 2 -NiO nanocomposites with varying molar ratio (Sn:Ni = 1:3, 1:1, 3:1) were synthesized by a citric acidassisted hydrothermal route and sintered over a YSZ-electrolyte to form the sensing electrode of the sensor. The phase structure and morphology of the electrodes were characterized by powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM) techniques. The NO 2 sensing performance of the fabricated sensor was measured at 700°C with varying NO 2 and O 2 concentrations. Furthermore, the electrochemical polarization curves were studied for the analysis of the sensing mechanism. It was found that the sensing response ( V), sensitivity, response/recovery dynamics as well as cross-sensitivity of these sensors were greatly dependent over the cationic molar ratio (Sn: Ni) of the nanocomposite sensing electrode. Moreover, the SnO 2 -NiO nanocomposites displayed high sensitivity, high stability and low cross-sensitivity; projecting it as a potential sensing electrode material for the electrochemical NO 2 sensors.

Recent Advances in the Use of Biomass‐Derived Activated Carbon as an Electrode Material for Electroanalysis

“…[3,4] They are classified based on the method adopted for sensing, including optical, [5][6][7][8] electrochemical, [9,10] electrical, [11] thermometric, [12] mass sensitive, [13] magnetic [14][15][16] etc. They can also be classified based on the type of analyte into different types, including pH electrodes [17] and sensors for metal ions and determining gases, [18][19][20] as well as the mode of application into in vivo [21] and in vitro [22] sensors for process monitoring. Among these methods, electrochemical methods possess remarkable features, such as high sensitivity, short response time, low cost, simplicity of instrumentation, the possibility of miniaturization, and integration with portable devices.…”

“…They are classified based on the method adopted for sensing, including optical, [5–8] electrochemical, [9,10] electrical, [11] thermometric, [12] mass sensitive, [13] magnetic [14–16] etc. They can also be classified based on the type of analyte into different types, including pH electrodes [17] and sensors for metal ions and determining gases, [18–20] as well as the mode of application into in vivo [21] and in vitro [22] sensors for process monitoring.…”

Recent Progress on Nanomaterials for NO2 Surface Acoustic Wave Sensors

“…In recent years, different types of NO 2 sensors have been developed based on sensing materials, fabrication technologies, input signals and conversion mechanism or sensor features (such as cost, stability or accuracy). Most studied NO 2 sensors are metal oxide semiconductor sensors [4][5][6][7], catalytic-type sensors [8], electrochemical sensors [9,10] and acoustic-based sensors [11][12][13].…”

“…The main advantages of the electrochemical sensors include low power consumption, miniaturization and low cost. However, they operate in a limited temperature range and have moderate selectivity [9,15].…”

Thermal Stress Simulation and Structure Failure Analyses of Nitrogen–Oxygen Sensors under a Gradual Temperature Field

“…The O 2− involved in these reactions will migrate through the electrolytes and produce a responsive potential that can convert the NO x concentration signal to an electrical signal [10,11]. Reactions (2) and (4) indicate that the nitrogen-oxygen sensor exhibits opposite response potential signals when detecting NO and NO 2 , because O 2− moves in the opposite direction: the sensor produces a positive potential signal when detecting NO 2 and a negative potential signal when detecting NO.…”