Preparation and Characterization of Ca₃(Co,M)₄O_9+δ Type Thermoelectric Materials Using the Electrostatic Spray Deposition Method

Abstract

ABSTRACT

Ca₃(Co_1−xAl_x)₄O_9+δ, Ca₃(Co_1−yCu_y)₄O_9+δ, Ca₃(Co_1−x−yAl_xCu_y)₄O_9+δ thin-films and sintered bodies were prepared using the electrostatic spray deposition method. Electrical conductivity of Ca₃(Co_0.95Al_0.025Cu_0.025)₄O₉ showed large values compared with Ca₉Co₁₂O₂₈. Power factor of Ca₃(Co_0.95Al_0.025Cu_0.025)₄O₉ also showed approximately same values as those of single phase compounds of Ca₉Co₁₂O₂₈. It was considered that the phenomenon was due to the increase of hole concentration and its mobility.