Electrical transport and thermoelectric properties of Ni-doped perovskite-type YCo_(1-x)Ni_xO_3 (0 ≤ x ≤ 0.07) prepared by sol-gel process  

作　　者：刘义 李海金 张清 李勇 刘厚通 

机构地区：[1]School of Mathematics and Physics,Anhui University of Technology

出　　处：《Chinese Physics B》2013年第5期456-461,共6页中国物理B（英文版）

基　　金：Project supported by the Key Laboratory of Novel Thin Film Solar Cells, Chinese Academy of Sciences (Grant No. KF201101);the Key Science Foundation of Higher Education Institutions of Anhui Province, China (Grant Nos. KJ2011A053 and KJ2012Z034);the National Natural Science Foundation of China(Grant Nos. 51202005, 11204005, and 41075027)

摘　　要：Electrical transport and thermoelectric properties of Ni-doped YCOl-xNixO3 （0 ≤ x ≤0.07）, prepared by using the sol-gel process, are investigated in a temperature range from 100 to 780 K. The results show that with the increase of Ni doping content, the values of DC resistivity of YCo 1-xNixO3 decrease, but carder concentration increases. The temperature dependences of the resistivity for YCOl-xNixO3 are found to follow a relation of lnp o, lIT in a low-temperature range （LTR） （T 〈- 304 K for x = 0; - 230 K 〈 T 〈- 500 K for x = 0.02, 0.05, and 0.07） and high-temperature range （HTR） （T 〉-655 K for all compounds）, respectively. The estimated apparent activation energies for conduction Eal in LRT and Ea2 in HTR are both found to decrease monotonically with doping content increasing. At very low temperatures （T 〈-230 K）, Mott＇s law is observed for YCOl-xNixO3 （x≥ 0.02）, indicating that considerable localized states form in the heavy doping compounds. Although the Seebeck coefficient of the compound decreases after Ni doping, the power factor of YCOl-xNixO3 is enhanced remarkably in a temperature range from 300 to 740 K, i.e., a 6-fold increase is achieved at 500 K for YCo0.98Ni0.0203, indicating that the high-temperature thermoelectric property of YCoO3 can be improved by partial substitution of Ni for Co.Electrical transport and thermoelectric properties of Ni-doped YCOl-xNixO3 （0 ≤ x ≤0.07）, prepared by using the sol-gel process, are investigated in a temperature range from 100 to 780 K. The results show that with the increase of Ni doping content, the values of DC resistivity of YCo 1-xNixO3 decrease, but carder concentration increases. The temperature dependences of the resistivity for YCOl-xNixO3 are found to follow a relation of lnp o, lIT in a low-temperature range （LTR） （T 〈- 304 K for x = 0; - 230 K 〈 T 〈- 500 K for x = 0.02, 0.05, and 0.07） and high-temperature range （HTR） （T 〉-655 K for all compounds）, respectively. The estimated apparent activation energies for conduction Eal in LRT and Ea2 in HTR are both found to decrease monotonically with doping content increasing. At very low temperatures （T 〈-230 K）, Mott＇s law is observed for YCOl-xNixO3 （x≥ 0.02）, indicating that considerable localized states form in the heavy doping compounds. Although the Seebeck coefficient of the compound decreases after Ni doping, the power factor of YCOl-xNixO3 is enhanced remarkably in a temperature range from 300 to 740 K, i.e., a 6-fold increase is achieved at 500 K for YCo0.98Ni0.0203, indicating that the high-temperature thermoelectric property of YCoO3 can be improved by partial substitution of Ni for Co.

关 键 词：perovskite cobalt oxides sol-gel process electrical transport thermoelectric property 

分 类 号：O482.4[理学—固体物理]