Thin film technology, solid electrolytes

Intermediate Temperature Solid Oxide Fuel Cell (ITSOFC) The electrolyte and electrode materials in this fuel cell are basically the same as used in the TSOFC. The ITSOFC operates at a lower temperature, however, typically between 600 to 800°C. For this reason, thin film technology is being developed to promote ionic conduction alternative electrolyte materials are also being developed. 

Xie D, Jiang YD, Pan W, Li D, Wu ZM, Li YR (2002) Fabrication and characterization of polyanUine-based gas sensor by ultra-thin film technology. Sens Actuators B 81 158-164 Yasuda A, Doi K, Yamaga N, Fujioka T, Kusanagi S (1992) Mechanism of the sensitivity of the planar CO sensor and its dependency on humidity. J Electrochem Soc 139 3224-3229 Zawodzinski TA, Springer TE, Uribe F, Gottesfeld S (1993) Characterization of polymer electrolytes for fuel cell applications. Solid State Ionics 60 199-211... 

Solid-state electrochemistry — is traditionally seen as that branch of electrochemistry which concerns (a) the -> charge transport processes in -> solid electrolytes, and (b) the electrode processes in - insertion electrodes (see also -> insertion electrochemistry). More recently, also any other electrochemical reactions of solid compounds and materials are considered as part of solid state electrochemistry. Solid-state electrochemical systems are of great importance in many fields of science and technology including -> batteries, - fuel cells, - electrocatalysis, -> photoelectrochemistry, - sensors, and - corrosion. There are many different experimental approaches and types of applicable compounds. In general, solid-state electrochemical studies can be performed on thin solid films (- surface-modified electrodes), microparticles (-> voltammetry of immobilized microparticles), and even with millimeter-size bulk materials immobilized on electrode surfaces or investigated with use of ultramicroelectrodes. The actual measurements can be performed with liquid or solid electrolytes. 

In this electronic age, it is mandatory to use solid polymer electrolytes for different applications in science and technology. Polymer electrolytes can be shaped in the form of thin film, thereby reducing the internal resistance leading to application as gas sensing material. Few reports appeared on proton-conducting polymer films and their application to gas sensors [65]. 

In addition, the various types of polymer ionics can be easily fabricated into flexible thin films with large surface areas where the ions are free to move and can conduct electricity as in conventional liquid electrolytes. This has opened the challenging possibility of replacing the difficult to handle, often hazardous, liquid solutions by chemically inert, thin-layer membranes for the fabrication of advanced electrochemical devices. Particularly relevant in this respect has been the technological goal of replacing liquid electrolytes in lithium, non-aqueous batteries by a thin film of a solid polymer electrolyte which would act both as electrode separator and as a medium for ionic... 

The other approach is an attempt for a thinner electrolyte supported on a porous electrode. Recently, many researchers have been working on a thin-film-type SOFC to realize an intermediate-temperature fuel cell [6-9]. In this approach, the eleetrolyte must be supported on either the anode or cathode. The main diffieulty regarding this approach hes in making a solid thin film on a porous electrode. To get a dense electrolyte layer, the electrolyte thickness should be several times larger than the maximum pore size of the support electrode. Thus, the preparation method of the support electrode with good pore-size distribution is a key technology of this approach not only it is difficult, but... 

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