Solid-state gas sensors

A. Mandelis, and C. Christofides, Solid State Gas Sensor Devices, in Chemical Analysis, John Wiley Sons, New York (1993). 

Table 6.7 Potentiometric solid-state gas sensors (adapted from Fouletier, 1982)... 

In this review the basis for the chemical sensitivity of these devices will be explored and the various device structures used for these sensors will be discussed. A survey of the performance of the diode-type and capacitor-type structures will be presented and a comparison of characteristics of these two classes of solid state gas sensors will be given. 

Scheidtmann, J. Frantzen, A. Frenzer, G. Maier, W. F., A combinatorial technique for the search of solid state gas sensor materials, Meas. Sci. Technol. 2005, 16, 119-127... 

A second group of solid-state gas sensors is constituted by those involving equilibration with the mobile component of solid electrolyte. A typical example is COt sensor with K2CO3 solid electrolyte. Here, K ions are the only mobile ions in the solid electrolyte, so that the overall electrochemical process can be represented as (Pasierb and Rekas, 2009) ... 

Dutta, A., Ishihara, T. and Nishiguchi, H. (2004) An amperometric solid-state gas sensor using a LaGaOj-based perovskite oxide electrolyte for detecting hydrocarbon in exhaust gas. A bimetallic anode for improving sensitivity at low temperatures. Chem. Mater., 16 (24), 5198-204. 

Further development of new impedance-based gas sensors is likely to allow their introduction to niche applications in the field of zirconia-based, solid-state gas sensors. Impedance spectroscopy has the potential to measure changes not detectable with simple current or voltage measurements. Although it is not practical to implement complete impedance spectroscopy in an operating sensor, an optimized frequency suitable for a specific gas sensor may be used. So far, these sensors are still more complex and expensive as compared to the potentiometric zirconia-based gas sensors. However, they have two important advantages (1) measurement of total NOx concentration, regardless of the NO/NO2 ratio in exhausts and (2) near equal sensitivity to NO and NO2 at 700°C. These are essential prerequisites to their practical implementation in vehicle exhausts. Therefore, further investigation is... 

Jones T A, Bott B, Hurst N W and Mann B 1983 Solid state gas sensors zinc oxide single crystals and metal phthalocyanine films Proc. Int. Meeting on Chemical Sensors (Analytical Chemistry Symposia Series 17, Fukuoda 1993) ed T Seiyama, K Fueki, J Shiokawa and S Suzuki (New York Elsevier) pp 90-4 Saeki H and Suzuki S 1992 Organic thin film semiconductor device Japanese Patent IPX 19881102 63-277732 US Patent 3 Q19 595 Lewis A 1967 The Palladium Hydrogen System (New York Academic)... 

In different studies, it was recognised that mine detection by EN in the field conditions is limited by the parameters of the sensors. An increase of the sensitivity of the devices seems to be the primary task of most current developments, because veiy small amounts of the characteristic volatile compounds (mostly in ppb or even sub-ppb intervals) have to be traced and recognised in gas mixture. Another limitation for the EN applications is related to comparatively long response time of the sensors when small amounts of the chemicals are to be detected. Low rate of adsorption and desorption process for complex volatile compounds seems the main problem in reduction of the detection time in EN especially when it includes solid-state gas sensors. 

This report deals with the dynamic response of the solid-state gas sensors when the gaseous composition of the atmosphere is intentionally varied. The study is focused on the featuring of the chemical composition of the atmosphere using the information extracted from the transients of the response. Theoretical analysis of the surface processes in the sensors is aimed at a description of the response kinetics by a set of the parameters acceptable for the featuring of an odour. The method was tested by experimental investigations of the response kinetics under exposure to various volatile compounds including that Ifom TNT based explosives. 

Examples of Potentiometric Gas Analysis with Solid-State Gas Sensors. 1134... 

This review is written from the point of view of a chemist who is interested in sensors rather than from that of one whose main interest is the analysis of gases as a discipline in its own right. Therefore although the current literature on solid state gas sensors greatly outnumbers that on membrane type sensors this review concentrates on the latter. The reader interested in solid state devices is referred to a number of excellent reviews and conference proceedings which have appeared recently [5-9]. 

A. M. Taurino, R. Rella, J. Spadavecchia, M.G. Manera, S. Capone, M. Martino, A.P. Caricato, T. Tunno, Acetone and ethanol solid-state gas sensors based on Ti02 nanoparticles thin film deposited by matrix assisted pulsed laser evaporation , Sensors and Actuators B, 127, 426 31, (2007). 

Solid-State Gas Sensors for Detecting Environmental Gases... 

Gas sensors for detecting the atmospheric environment must be able to operate stably under deleterious conditions, including chemical and/or thermal attack. Therefore, solid-state gas sensors would appear to be the most appropriate in terms of their practical robustness. Yamazoe describes a gas sensor as a device that basically performs two functions the receptor and the transducer functions... 

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