Evaluation of Thermoelectric Properties of Doped β-Iron Disilicide Prepared by the Powder Metallurgy Technique

Abstract

Thermoelectric generator (TEG) offers a potential application in harvesting waste-heat energy into usable electrical power. β-iron disilicide (β-FeSi2) thermoelectric is applicable in elevated temperature systems such as hydrogen plants, copper reverberatory furnace and copper refining furnace. In this work, high TE performance Mn doped p-type and Co doped n-type thermoelectric (TE) β-iron disilicide compacts were fabricated for TEG using powder metallurgy route. The effects of variation in type and quantity of dopants [p-type dopant: Mn: stoichiometry Fe1−xMnxSi2 (x = 0.04 − 0.12) or n-type dopant: Co: stoichiometry Fe1−yCoySi2 (y = 0.01 − 0.05)] on thermoelectric properties were studied. Significant improvement in ZT was observed compared to earlier research works for this material system. This result is a positive indication for the potential use of β-FeSi2 in the high temperature TEG. In this work, the working efficiency was also evaluated which was not mentioned in the earlier research works.