Energy Transformation by temperature difference is performed using thermoelectric semiconductor and is crucial issue to employ exhaust heat in our daily life. A metal oxide has been popular now besides metal compound like Bi_2Te_3. Unfortunately, an oxide seems to be low electrical conductivity in general. However, an oxide has high thermoelectric power (Seebeck coefficient) and relatively low thermal conductivity. We study rutile-TiO_2 to decrease electrical resistivity during maintaining higher Seebeck coefficient and lower thermal conductivity. Electrical resistivity of 1 wt percent added-TiO_2 was 2.7 X 10~(-5) OMEGA m around 700K meaning 45 percent reduction. As a result, power factor for the specimen was the highest which was 1.4 X 10~(-3)around 700K, 1.4 times larger than the none-added specimen (standard). The effective charge of Fe was 1.88 and Ti was 2.42 ,meaning that the electrons seemed to move to Fe. Transport coefficient of thermoelectricity was also discussed associating with Onsager's equation
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