l' article de Nature qui a inspiré l' article ci dessus est ici :
http://www.nature.com/news/out-of-disor ... ty-1.11445
je reléve :
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Kanatzidis and his team began with one of the most well-known thermoelectrics: lead telluride (PbTe), which usually has an ordered lattice structure. The researchers scattered in a few sodium atoms to boost the material's electrical conductivity, then shoved in some nanocrystals of strontium telluride (SrTe), another thermoelectric material. The crystals allowed electrons to pass, but disrupted the flow of heat at short scales, preserving the temperature gradient.
The final step was to stop heat flow over longer scales. To do this, the team created a fractured version of their pretty thermoelectric crystal. The fracturing did the trick: the cracks allowed electrons to move but reflected heat vibrations in the crystal. The material had a conversion efficiency of about 15% — double that of normal PbTe thermoelectrics.
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ils partent de Tellure de Plomb, et aprés la recette de cuisine est un peu alambiquée.
ensuite :
That doesn't mean that the material is ready to be used on the next Mars rover, Snyder adds. The sodium introduced to make electrons move is highly reactive, and can degrade the material, particularly if it accumulates along the fractures designed to stop heat flow. NASA has been looking at similar approaches for future space missions, but the agency is not yet convinced that the approach is ready for launch, he says.
Kanatzidis is more optimistic. "I think the materials that we have today are good enough for applications," he says. "My belief is that in about two to three years we will have something."
bon si il est persuadé que dans 2 ou 3 ans on aura ''quelque chose'', ca veut dire qu' il faut en compter 10 pour que ca arrive sur le marché industriel.
