Fabrication and Thermoelectric Properties of Magneli Phases by Adding Ti into TiO₂

Abstract:

In the present study, the TiO₂-Ti compacts with Magneli phases Ti_nO_2n-1 were fabricated using the mixed powder of TiO₂ powder and addition Ti powder by spark plasma sintering (SPS). The composition and the crystal types of Magneli phases Ti_nO_2n-1 were examined. The results showed that various Magneli phases Ti_nO_2n-1 (single or multi Magneli phases) with the composition of Ti_1+yO_2-x were obtained. The Magneli phases Ti_nO_2n-1 were formed in the transformation from the mother phase rutile TiO₂ to TiO with increase in Ti addition fraction. In addition, the thermoelectric properties of the sintered compacts were also measured. The electrical resistivity of the sintered compacts decreased with increase in Ti addition fraction. The thermoelectric performance of the sintered compacts was improved by the formation of Magneli phases Ti_nO_2n-1 with the composition of Ti_1+yO_2-x.

• Periodical: Advanced Materials Research (Volumes 415-417)
• Pages: 1291-1296
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.415-417.1291
• Online since: December 2011
• Authors: Yun Lu, Yusuke Matsuda, Katsuhiro Sagara, Liang Hao, Takahito Otomitsu, Hiroyuki Yoshida
• Keywords: Magneli Phase, Nonstoichiometric Compound, Spark Plasma Sintering (SPS), Thermoelectric Property, TiO₂, Titanium Addition

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