Carbonate solid electrolyte sensors

Imanaka N, Kamikawa M, Tamura S, Adachi G (2001) Carbon dioxide gas sensor with multivalent cation conducting solid electrolytes. Sensor Actuat B 77 301-306... 

Kaneyasu, J. Otsuka, K. Setoguchi, Y. Sonoda, S. Nakahara, T. Aso, I. Naka-gaichi, N. A carbon dioxide gas sensor based on solid electrolyte for air quality control. Sensors and Actuators B, 66 (2000) 1-3, p. 56-58. 

Recent Developments in Electrochemical Solid Polymer Electrolyte Sensor Cells for Measuring Carbon Monoxide and Oxides of Nitrogen... 

Instead of the system silica/silicate also other systems such as titania/titanate, zirconia/zirconate can be used as a reference system [xiv]. The response time of freshly fabricated thick-film sensors based on thin-film /3-alumina is very short (about 15 ms at 650 °C). After several weeks of operating this time increases 10 times (150 ms) [xv]. Solid electrolyte C02 sensors using Ni/carbonate composite as measuring electrode are suited for measuring of C02 in equilibrated water gases [xiv]. Using semiconducting oxides and carbonates like ITO (indium tin oxide) Nasicon-based C02 sensors are able to measure at room temperature [xvi]. 

Satyanarayana, L., Choi, G.P., Noh, W.S., Lee, W.Y and Park, J.S. (2007) Characteristics and performance of binary carbonate auxiliary phase CO2 sensor based on Li3PO4 solid electrolyte. Solid State Ionics, 177 (39-40). 3485-90. 

Yao, S., Shimizu. Y.. Miura, N. and Yamazoe. N. (1995) Solid electrolyte carbon dioxide sensor using sodium ionic conductor and lithium carbonate-based auxiliary phase. Appl. Phys. A.. 57. 25-9. 

Ikeda, S., Kondo, T. Kato, S., Ito, K., Nomura, K. and Fujita, Y. (1995) Carbon dioxide sensor using solid electrolytes with zirconium phosphate framework (2). Properties of the CO, gas sensor using Mgi.i5Zr4P5 7810.30,4 as electrolyte. Solid-State Ionics, 79, 354—7. 

Thermodynamic equilibria are also of principal importance, if one wishes to determine carbon dioxide or sulfur dioxide with carbonates or sulfates which show conductance for sodium or potassium ions. It is not the ion migrating through the solid, but the electrochemical equilibrium between molecules in the gas phase, particles in the solid electrolyte and electrons in the electrical conductor that determine the electrode potential utilizable in sensors. 

The simplest type of sensors with oxoanionic solid electrolytes is the one with alkali carbonates. The electrode reaction (25-66) on both sides produces the following cell reaction ... 

Figure 25-29. Signals from a hot solid-electrolyte gas sensor as a detector behind a gas-chromatographic column analyzing two portions of technical carbon monoxide. The carrier gas was nitrogen with a very small oxygen concentration [85]. In the first run the sample was mixed with air.

Carbon dioxide is chemically inactive so that some kind of sensors such as the semiconductor sensor is not adequate to detect CO, because the semiconductor sensor operates on the principle based on chemical reaction of gases at the surface. Most of simple and handy sensors are based on the effect of adsorption, desorption and electrochemical reaction. In Table 7, current status of CO, sensors are summarized together with the requirement of environmental monitoring and conventional analytical equipments[6]. Recently, electrochemical sensors, especially solid electrolyte CO, sensors have been actively studied and developed[56-63]. 

In Type III, there is an auxiliary phase attached on the surface of the solid electrolyte so as to be sensitive to the gas, and it is produced by a compound that contains the same ionic species as derived from the gas. The auxiliary phase can act as a sort of poor ion-conducting solid electrolyte, which forms a half cell of Type I or II as shown in Figure 1.1 [1]. Type III sensors can be divided into three subgroups depending on the types of the half cells combined [6]. Since a NASICON solid electrolyte potentiometric gas sensor using alkali metal carbonate as an auxiliary phase solid electrolyte is known to be sensitive to CO2, Type III sensors have been of immense importance as sensors for oxygenic gases such as CO2, NOx, and SOx... 

Yao S., Shimizn Y, Minra N., and Yamazoe N., Solid electrolyte CO2 sensor nsing binary carbonate electrode, Chem. Lett., 18, 2033-2036, 1990. 

Nitrogen dioxide can also be selectively detected by an electrode with a chalcogenide (Se6oOe28Sbi2) membrane, without interference from nitric oxide, sulfur dioxide, carbon monoxide, methane, and other gases. Another solid-state sensor for NO2 employs an alkaline nitrate electrolyte at a temperature of 800°C. 

Santhosh P, Manesh KM, Gopalan A, Lee K-P (2007) Novel amperometric carbon monoxide sensor based on multi-wedl carbon nanotubes grafted with polydiphenylamine-fabrication and performance. Sens Actuators B 125 92-99 Shai K, Wagner J (1982) Enhanced ionic conduction in dispersed solid electrolyte systems (DSES) and/or multiphase systems Agl-Al Oj, Agl-SiO, Agl-Ely ash, and Agl-AgBr. J Sohd State Chem 42 107-119 Shimizu Y, Yamashita N (2000) Solid electrolyte CO sensor using NASICON and perovskite-type oxide electrode. Sens Actuators B 64 102-106... 

A similar situation occurs with sensors based on several types of solid electrolytes (Fergus 2008). For example, carbonate and sulfate electrolytes could be used with CO and SO sensors. However, those electrolytes generally do not provide adequate stability (see Chap. 6 (Vol. 1)), and therefore the most promising sensors use common electrolytes, such as Nasicon, P-alumina, and yttria-stabilized zirconia (YSZ). These electrolytes require auxiliary electrodes to provide the desired response, but they provide good stability and long operating lives. Therefore, while optimizing the reactions responsible for a gas sensor s sensitivity, one should also aim to maximize the chemical, structural and time stability of the device. 

Maruyama T, Sasaki S, Saito Y (1987) Potentiometric gas sensor for carbon dioxide using solid electrolytes. Solid State Ionics 23 107-112... 

Miura N, Yao S, Shimizy Y, Yamazoe N (1992) High-performance solid-electrolyte carbon dioxide sensor with a binary carbonate electrode. Sens Actuators B 9 165-170... 

Miura N, Yan Y, Sato M, Yao S, Nonaka S, Shimizu Y, Yamazoe N (1995) Solid state potentiometric CO sensors using anion conductor and metal carbonate. Sens Actuators B 24-25 260-265 Miura N, Lu G, Yamazoe N (2000) Progress in mixed-potential type devices based on solid electrolyte for sensing redox gases. Solid State Ionics 136-137 533-542... 

Yao S, Shimizu Y, Miura N, Yamazoe N (1990) Solid electrolyte CO sensor using binary carbonate electrode. Chem Lett 1990 2033-2036... 

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