Thermoelectric characterization of fine-grained Ti5O9 Magneli phase   ceramics
  Magneli phase Ti5O9 ceramics with 200-nm grain-size were fabricated by hot-pressing nanopowders of titanium and anatase TiO2 at 1223 K. The thermoelectric properties of these ceramics were investigated from room temperature to 1076 K. We show that the experimental variation of the electrical conductivity with temperature follows a small-polaron model and that the Seebeck coefficient can be explained by a temperature-dependent Heikes-Chaikin-Beni model. The thermoelectric figure-of-merit ZT of this nanoceramic material reaches 0.3 at 1076 K. 
Sudeep Jung Pandey and Giriraj Joshi and Shidong Wang and Stefano   Curtarolo and Romain Gaume
cond-mat.mtrl-sci