Integrated synthesis of AMTEC electrode by using controlled thermal plasma processing

Thermoelectric materials (beta"-alumina) for the alkali metal thermoelectric converter (AMTEC) have been synthesized with the use of a thermal plasma reactor based on the forced constricted type plasma jet generator. It is reconfirmed that the powder mixing ratio (i.e. the ratio between alpha-Al2O3, Na2CO3 and MgO), jet power and substrate position, strongly affect the synthesis of beta"-alumina. Besides these, the synthesis of beta"-alumina is also enhanced in the high-temperature region by oxygen injection. Those dependences are correlated with jet temperature and particle heating. The metal elect-rode of molybdenum is also prepared by spraying Mo powders. Porosity of the prepared films could be well controlled by varying the Pressure. (C) 2002 Elsevier Science B.V. All rights reserved.