Abstract: Rare earth La doping ZrO₂ and composite La₂Zr₂O₇/ZrO₂ were synthesized by in situ synthesis method with Zr(NO₃)⁴•3H₂O,La(NO₃)³•6H₂O,and C₆H₈O₇•H₂O as raw materials.Phase composition and high temperature stability of the products were studied by analysis means of XRD and Raman.Results indicated that it was difficult for La to enter crystal lattice of ZrO₂ being solid solution,when the doping amounts of La were less,rare earth doping ZrO₂ was composed of m-ZrO₂ and La₂Zr₂O₇;when the doping amounts of La were more,rare earth doping ZrO₂ was composed of t-ZrO₂ and La₂Zr₂O₇.The t-ZrO₂ was converted into m-ZrO₂ in LZZ11 (the sample prepared on the proportion of 1∶1 of La₂Zr₂O₇ and ZrO₂ in amount-of-substance ratio) by calcining at 1 400 ℃ for 6 h,and it was clear that La₂Zr₂O₇ was no conducive to the stabilizing of ZrO₂. 

Key words: rare earth doping, La₂Zr₂O₇/ZrO₂ composite material, phase composition, high temperature stability