Study of YSZ-Based Electrochemical Sensors with WO[sub 3] Electrodes in NO[sub 2] and CO Environments

Dutta, Atanu; Kaabbuathong, Narin; Grilli, Maria Luisa; Bartolomeo, Elisabetta Di; Traversa, Enrico

doi:10.1149/1.1533044

Cited by 75 publications

(68 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, value of the emf measured for 200 ppm NO 2 was ≈ 90 mV in the present experiments which is more than two times higher than in previous results [12,13].…”

Section: -2-2 Sensing Propertiescontrasting

confidence: 73%

“…Among the above oxides, WO 3 is of particular interest because it has been known to be sensitive to NO x without significant sensor signal drift. According to earlier studies, the potentiometric response to NO x using a WO 3 electrode was fast and stable, and a linear relationship was obtained in a plot of the sensor emf vs. the logarithm of NO x concentration [12,13].…”

Section: Differential Electrode Equilibriamentioning

confidence: 96%

See 1 more Smart Citation

MULTIFUNCTIONAL (NOx/CO/O2) SOLID-STATE SENSORS FOR COAL COMBUSTION CONTROL

Wachsman¹

2005

View full text Add to dashboard Cite

We have made great progress in both developing solid state sensors for coal combustion control and understanding the mechanism by which they operate. We have fabricated and tested numerous sensors and identified the role electrode microstructure plays in sensor response. We have developed both p-type (La 2 CuO 4 ) and n-type (WO 3 ) semiconducting NO x sensing electrodes. We have demonstrated their respective sensing behavior (sensitivities and cross-sensitivities), related this behavior to their gas adsorption/desorption behavior and catalytic activity, and in so doing verified that our proposed Differential Electrode Equilibria is a more comprehensive sensing mechanism.These investigations and their results are summarized below.The composition and microstructure of the sensing electrode is the key parameters that influence the sensing performance. We investigated the effect of electrode microstructure on the NO x sensitivity and response time using a La 2 CuO 4 -based potentiometric sensor.Temperature dependence, cross-sensitivity and selectivities of a La 2 CuO 4 -and WO 3 -based potentiometric NO x sensor were investigated both in N 2 and in a simulated exhaust gas. We performed temperature programmed reaction (TPR) and desorption (TPD) experiments to determine the reaction and adsorption characteristics of O 2 , NO x , CO, CO 2 , and their mixtures on the electrodes, and related the results to sensor performance.In order to optimize the sensor electrode microstructure, powders were prepared using four different powder synthesis routes, resulting in different particle size distributions and BET surface areas. Different sintering conditions were also applied. The microstructure of electrodes, synthesized with the same composition, has a dramatic effect on both sensitivity and response time of potentiometric NO sensors, showing that large surface areas generate a porous morphology with smaller grain size, and that smaller grain size results in a sharper response and faster response time.The relative responses of the La 2 CuO 4 -based sensor under varied concentrations of NO, NO 2 , CO, CO 2 and O 2 were studied. The results showed a very high sensitivity to NO, CO, and NO 2 at 450 ºC in 3% O 2 , whereas the response to O 2 and CO 2 gases was negligible.The NO response at 400 -500 ºC agreed with the NO adsorption behavior. The high NO 2 iv sensitivity at 450 ºC was probably related to heterogeneous catalytic activity of La 2 CuO 4 .The adsorption of NO was not affected by the change of O 2 concentration and thus the sensor showed selective detection of NO over O 2 . However, the NO sensitivity was strongly influenced by the existence of CO, H 2 O, NO 2 , and CO 2 , as the adsorption behavior of NO was influenced by these gases.The WO 3 -based sensor was able to selectively detect NO in the presence of CO 2 in 3% O 2 at 650 ºC. The NO sensitivity, however, was affected by the variation of the NO 2 , CO, and H 2 O concentration. No gas-solid reactions were observed using TPR in the NOcontaining gas mixtur...

show abstract

“…For example, value of the emf measured for 200 ppm NO 2 was ≈ 90 mV in the present experiments which is more than two times higher than in previous results [12,13].…”

Section: -2-2 Sensing Propertiescontrasting

confidence: 73%

Section: Differential Electrode Equilibriamentioning

confidence: 96%

MULTIFUNCTIONAL (NOx/CO/O2) SOLID-STATE SENSORS FOR COAL COMBUSTION CONTROL

Wachsman¹

2005

View full text Add to dashboard Cite

show abstract

“…According to earlier studies, the potentiometric response to NO x using a WO 3 electrode was fast and stable. Furthermore, this type of sensor had a linear relationship between the sensor electromotive force (EMF) and the logarithm of NO x concentration [14,15 ].…”

Section: Differential Electrode Equilibriamentioning

confidence: 99%

Multifunctional (NOx/CO/O2) Solid-State Sensors For Coal Combustion Control

Wachsman¹

2006

View full text Add to dashboard Cite

Solid-state sensors were developed for coal combustion control and the understanding of sensing mechanisms was advanced. Several semiconducting metal oxides (p-type and n-type) were used to fabricate sensor electrodes. The adsorption/desorption characteristics and catalytic activities of these materials were measured with Temperature Programmed Desorption (TPD) and Temperature Programmed Reaction (TPR) experiments. The sensitivity, selectivity, and response time of these sensors were measured for steps of NO, NO 2 , CO, CO 2 , O 2 , and H 2 O vapor in simple N 2 -balanced and multi-component, simulated combustion-exhaust streams.The role of electrode microstructure and fabrication parameters on sensing performance was investigated. Proof for the proposed sensing mechanism, Differential Electrode Equilibria, was demonstrated by relating the sensing behavior (sensitivities and cross-sensitivities) of the various electrode materials to their gas adsorption/desorption behaviors and catalytic activities.A multifunctional sensor array consisting of three sensing electrodes and an integrated heater and temperature sensors was fabricated with tape-casting and screen-printing and its NO x sensing performance was measured. The multifunctional sensor demonstrated it was possible to measure NO 2 independent of NO by locally heating one of the sensing electrodes.The sensor technology was licensed to Fuel FX International, Inc. Fuel FX has obtained investor funding and is developing prototype sensors as a first step in their commercialization strategy for this technology.iv

show abstract

“…Thus, there is a need for inexpensive and portable sensors in various fields. Although semiconductor gas sensors as well as electrochemical sensors have been developed to determine the concentration of NO, (3)(4)(5)(6)(7) in general, they are poor at distinguishing NO from NO 2 .…”

Section: Introductionmentioning

confidence: 99%

Nitric Oxide Gas Sensors Using Multilayered Thin Film with Interspaces

2018

Sensors and Materials

View full text Add to dashboard Cite

Nitric oxide (NO) is an air pollutant known to adversely affect the environment, humans, and other living organisms. Low-level NO gas is also created by human bodies and emitted as a component of exhaled breath and skin gas under some health conditions. Therefore, there is a strong demand for the monitoring of NO gas concentration. In this paper, we present novel NO gas sensors that have been developed using multilayered WO 3 -based thin films with interspaces. Ag doping into a WO 3 thin film is effective in increasing the sensitivity to NO. Multilayered thin-film sensors with interspaces successfully enhance both sensitivity and selectivity to NO. The developed sensor with quadruple-layered sensing films can detect as low as 0.5 ppm NO gas with good selectivity at an operating temperature of 290 ℃. The response and recovery times are 81 and 138 s, respectively, for the double-layered sensor, while its sensitivity is lower than that of the quadruple-layered sensor. Thus, the sensors are promising as a portable and inexpensive NO sensing device in various application fields such as environmental monitoring and health diagnosis.

show abstract

Study of YSZ-Based Electrochemical Sensors with WO[sub 3] Electrodes in NO[sub 2] and CO Environments

Cited by 75 publications

References 26 publications

MULTIFUNCTIONAL (NOx/CO/O2) SOLID-STATE SENSORS FOR COAL COMBUSTION CONTROL

MULTIFUNCTIONAL (NOx/CO/O2) SOLID-STATE SENSORS FOR COAL COMBUSTION CONTROL

Multifunctional (NOx/CO/O2) Solid-State Sensors For Coal Combustion Control

Nitric Oxide Gas Sensors Using Multilayered Thin Film with Interspaces

Contact Info

Product

Resources

About