TY - JOUR
T1 - High thermoelectric performance of dually doped ZnO ceramics
AU - Ohtaki, Michitaka
AU - Araki, Kazuhiko
AU - Yamamoto, Kiyoshi
N1 - Funding Information:
This work was partly supported by Grant-in-Aid for Scientific Research (B) (18360318) and Grant-in-Aid for Exploratory Research (20656105), the Ministry of Education, Culture, Sports, Science, and Technology (MEXT), Japan.
PY - 2009/7
Y1 - 2009/7
N2 - A marked improvement in the thermoelectric performance of dense ZnO ceramics is achieved by employing a third element as a co-dopant with Al. Dual doping of ZnO with Al and Ga results in a drastic decrease in the thermal conductivity of the oxide, while the decrease in the electrical conductivity is relatively small. With the aid of a significant enhancement in the thermopower, the dually doped oxide shows thermoelectric figure of merit values, ZT, values of 0.47 at 1000 K and 0.65 at 1247 K at the composition Zn 0.96Al 0.02Ga 0.02O. These results appear to be the highest ZT values so far reported for bulk n-type oxides. Microscopic observation of the samples reveals a granular texture in the densely sintered oxide matrix, suggesting that considerable reduction of the thermal conductivity while maintaining high electrical conductivity could be achieved by such a bulk nanocomposite structure in the samples.
AB - A marked improvement in the thermoelectric performance of dense ZnO ceramics is achieved by employing a third element as a co-dopant with Al. Dual doping of ZnO with Al and Ga results in a drastic decrease in the thermal conductivity of the oxide, while the decrease in the electrical conductivity is relatively small. With the aid of a significant enhancement in the thermopower, the dually doped oxide shows thermoelectric figure of merit values, ZT, values of 0.47 at 1000 K and 0.65 at 1247 K at the composition Zn 0.96Al 0.02Ga 0.02O. These results appear to be the highest ZT values so far reported for bulk n-type oxides. Microscopic observation of the samples reveals a granular texture in the densely sintered oxide matrix, suggesting that considerable reduction of the thermal conductivity while maintaining high electrical conductivity could be achieved by such a bulk nanocomposite structure in the samples.
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U2 - 10.1007/s11664-009-0816-1
DO - 10.1007/s11664-009-0816-1
M3 - Article
AN - SCOPUS:67650423947
VL - 38
SP - 1234
EP - 1238
JO - Journal of Electronic Materials
JF - Journal of Electronic Materials
SN - 0361-5235
IS - 7
ER -