Abstract |
Cu2Se exhibits very low thermal conductivity and the origin is known to be the "liquid-like" behavior of Cu ions around the sub-lattice of Se. Due to its very high ZT, research interest in the thermoelectric properties of this material has been increasing rapidly. However, most studies have used a conventional melting process, and, to the best of our knowledge, the melt-spinning process has not yet been employed to fabricate the Cu2Se compound. Herein, we report the thermoelectric properties of Cu1.98Se compounds prepared by melt-spinning. Depending on the cooling rate, we could control the microstructure of the melt-spun Cu1.98Se ribbons successfully. The melt-spun ribbons were consolidated using a hot press, and the thermoelectric properties of the compounds were characterized. Although the electrical conductivity of the compound decreased as compared with the Cu1.98Se compound prepared by the conventional method, an increase in Seebeck coefficient led to an improved power factor in the compound prepared by melt-spinning. Furthermore, a reduction in thermal conductivity due to the reduced contribution of electronic to total conductivity resulted in the enhancement of ZT values in the Cu1.98Se compound.
(Received May 3, 3018; Accepted May 23, 2018) |
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Key Words |
thermoelectric, Cu2Se, melt-spinning, hot pressing |
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