Electrolyte metal oxide oxygen sensor

The results of the present work may be applicable for diagnostics of oxygen sensors at more complicated applications, such as measurement of oxygen activity in liquid sodium, lithium, or lead-bismuth heat carriers for atomic power plants. Corrosion and mass transfer in nonisothermal lead-bismuth circuits with temperatures of a heat carrier of 300-500°C do usually occur at a concentration of dissolved O2 of 10 - 10 mass %. The proposed impedance method is developed for determining the level and the character of polarization at the electrolyte-electrode interface, which ensures a continuous oxide protection of materials against corrosion by means of zirconia sensors in all tanperature regimes of exploitation of liquid-metal circuits. 

Electronic and electrochemical detectors There are several different types of electronic or electrochemical detector for CO of which metal oxide semiconductor (MOS) sensors and electrolytic cells are the most common. In MOS detectors CO is oxidized on a heated tin oxide semiconductor where surface-adsorbed oxygen oxidizes gases such as CO and hydrocarbons producing electrons that enter the conduction band of the semiconductor thereby reducing its resistance ... 

The majority of solid electrolyte sensors are based on proton conductors (Miura et al. 1989, Alberti and Casciola 2(X)1). Metal oxides that can potentially meet the requirements for application in solid electrolyte sensors are listed in Table 2.7. These proton condnctors typically do not have high porosity but rather can reach 96-99% of the theoretical density (Jacobs et al. 1993). Similar to oxygen sensors, solid-state electrochemical cells for hydrogen sensing are typically constructed by combining a membrane of solid electrolyte (proton conductor) with a pair of electrodes (electronic conductors) Most of the sensors that use solid electrolytes are operated potentiometrically. The voltage produced is from the concentration dependence of the chenucal potential, which at eqnihbrium is represented by the Nemst equation (Eq. 2.3). 

Stoukides M (1988) Applications of solid electrolytes in heterogeneous catalysis. Ind Eng Chem Res 27 1745-1750 Subbarao EC, Maiti HS (1984) Sohd electrolytes with oxygen ion conduction. Sohd State Ionics 11 317-338 Sun J, Xu JY, Yu SP, Liu FG, Lu G (2012) UV-activated room temperature metal oxide based gas sensor attached with reflector. Sens Actuators B 169 291-296... 

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