Journal of Inorganic Materials ›› 2014, Vol. 29 ›› Issue (12): 1301-1305.doi: 10.15541/jim20140144

• Orginal Article • Previous Articles     Next Articles

Synthesis and Thermophysical Properties of (La1-xMgx)2Ce2O7-x

Bin YANG1,2(), Lin-Yan LI1(), Min-Guang FAN2, Bin LI2, Sheng-Ming XU1, Jian-Long WANG1, Xu-Ping LIN1   

  1. 1. Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China
    2. School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China
  • Received:2014-03-25 Revised:2014-05-17 Online:2014-12-20 Published:2014-11-20
  • About author:YANG Bin. E-mail: yangbin5170@126.com

Abstract:

Doping magnesium into La2Ce2O7 can increase its thermal expansion coefficient (TEC) and decrease its thermal conductivity (TC), thus improve its performance for thermal barrier coating (TBC). (La1-xMgx)2Ce2O7-x ceramics were prepared by Sol-Gel method. Powder X-Ray diffraction results revealed that (La1-xMgx)2Ce2O7-x showed the identical structure as La2Ce2O7 (defect-fluorite type), and the crystal parameter decrease with increasing x value in the range of 0≤x≤0.4, and MgO occurred in the product when x?0.4. The TEC of (La1-xMgx)2Ce2O7-x sample (0≤x≤0.4) with the same composition increases with the increasing temperature, whereas the TC presents the opposite trend. At the same temperature, the TEC of the (La1-xMgx)2Ce2O7-x sample (0≤x≤0.4) with different composition increases with increasing x value whereas the TC increases firstly and then decreases with the increasing of x value, where x=0.2 nearby as turning point. In addition, possible mechanisms of the influence of Mg doping on the structure, crystal parameter, TEC and TC of La2Ce2O7 are discussed.

Key words: La2Ce2O7, magnesium-doped, thermal expansion coefficient, thermal conductivity, thermal barrier coating ceramic

CLC Number: 

  • O641