1. School of Materials Science and Engineering， Hefei University of Technology， Hefei 230009， China 2. Electronic Engineering Institute， Hefei 230037， China
Abstract：[Ca2.95Sm0.05Co3.995-xNi0.005FexO9+δ][(х＝0，0.10，0.15，0.20)]ceramic material was prepared by self propagation process using citric acid as chelating agent， nitrate and oxide as oxidant. The synthesized powders [Ca2.95Sm0.05Co3.995-xNi0.005FexO9+δ][（x＝0.10）]were compacted. The thermoelectric properties of[Ca2.95Sm0.05Co3.995-x][Ni0.005FexO9+δ]were explored from 473 K to 973 K. The results show that the compression law of [Ca2.95Sm0.05Co3.995-x][Ni0.005FexO9+δ]is in accordance with HUANG Pei-yun equation with compaction module of 1.86 MPa and nonlinear exponent of 2.074， respectively. The electrical conductivity and Seebeck coefficient of the material increase with the increase of temperature， while the thermal conductivity decreases with the temperature increasing. The[ZT]value of [Ca2.95Sm0.05Co3.995-xNi0.005FexO9+δ]sample is 0.13 at 973 K.[Ca2.95Sm0.05Co3.995-xNi0.005FexO9+δ]is promising thermoelectric material.
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2017, Vol. 27 
