High-temperature electronic conductivity

Pure Co spinel (i.e., C03O4) also exhibits good high temperature electronic conductivity and CTE compatibility with ferritic steels 45 Deng et al.55 used a sulfate/chloride-based Co plating bath to coat... 

When water vapour or hydrogen is introduced to the atmosphere at high temperature, electronic conductivity decreases and protonic conduction appears. 

The ceramic interconnects used in higher temperature SOFCs are primarily doped lanthanum and yttrium chromites (dopants typically include Mg, Sr, Ca, Ca/Co). These perovskites are unique in that they exhibit high electronic conductivity and resist reduction under exposure to syngas at high temperatures. Electronic conductivity of these materials increases with temperature (making them unsuitable for use at low temperatures). At 1,000 °C the conductivities of these materials... 

At high temperature, the conductivity was found to increase linearly with temperature and the observed high-temperature MR was positive. In fact, by fitting the data using a simple two-band model] 17] the authors obtained the theoretical curve in Fig. 4 (a). The fitting parameters showed that the ratio Op/ct, where Op and are the partial conductivities of holes and electrons, respectively, decreases with increasing tern-... 

Silicon carbide (SiC) is an attractive semiconductor material for high temperature electronic and electro-optic applications. From the device application point of view the thermal conductivity of SiC exceeds that of copper, BeO, A1203 and AIN. The actual value of the thermal conductivity can be varied with polytype and/or doping [1,2]. 

The ceramic electrolyte is based on zirconia (Zr02) or ceria (Ce02), each of which is an electronic insulator but is conductive towards oxide ions (0 ) at high temperatures. This conductivity is achieved by doping the chosen oxide with ions of lower valency. For instance, when zirconia is doped with yttrium ions (Y ), oxide ion vacancies are formed in the parent lattice to compensate for the charge difference, i.e.,... 

Our approach is to separate the conduction paths for H+ ions and electrons through the incorporation of a ceramic second phase. This approach essentially eliminates the combined dependence of hydrogen flux on electronic and proton conductivities. The approach is to short-circuit the electron flow-paths so that the overall flux is limited only by the proton conductivity. A similar mixed conducting requirement exists for electrodes in high-temperature proton conducting fuel cells, and some work has been carried out to develop mixed conductors as electrodes [24]. 

Superconductors offer no resistance to the flow of electrons. The earliest known superconductors only exhibited the behavior at liquid helium temperature (4 K), but modem high-temperature superconductors conduct at temperatures as high as 140 K. 

Manufacturers Comments Silver-filied conductive adhesive (82-84% silver). High bond strengths. High temperature electronic uses. Low extractable corrosive ion content. Meets MIL-883 C Method 2019. ... 

At sufficiently high temperatures electrons are thermally excited from the valence into the conduction band. However, because of the high density of electron traps, their contribution to the charge transport is extremely low and p-type behavior prevails irrespective of a probably smaller electron effective mass. 

Ionic conductivity is electrical conductivity due to the motion of ionic charge. Elementary science introduces this phenomenon as a property of liquid electrolyte solutions. In the solid state, ionic conductivity has recently been somewhat overshadowed by electronic, but nevertheless was recognized by Faraday, who observed electrical conductivity in solid lead fluoride at high temperature. The conductivity in this case was due to the motion of fluoride anions within the structure. This type of conductivity in solids has long been of fundamental interest as well as being applied in the interpretation of corrosion. More recently, applications have been found in energy conversion devices and chemical sensors. ... 

---