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Different nanometer CeO_2-ZrO_2 mixed oxides doped with lanthanum or praseodymium were prepared by coprecipi-tation. The characteristics of all mixed oxides were tested by XRD, SEM, TEM, and XPS. XRD results showed thatall oxides were formed solid solution with CaF_2 structure at low temperature and had good thermal stability. MoreCe~(4+) ions were rich on the surface by XPS, which were beneficial to oxygen storage. The particle mediun sizes (d_(50))of all oxides powders were approximately 10～20 nm by small angle scattering goniometer. When doped Zr~(4+) inCeO_2, the specific surface areas were improved at low or high temperature. The area of Ce_(0.6)Zr_(0.3)La_(0.04)Pr_(0.06)O_2powder had excess 110 m~2/g after calcining at 923 K for 4 h, even calcined at 1273 K for 4 h, the area was up to65 m~2/g.
Different nanometer CeO_2-ZrO_2 mixed oxides doped with lanthanum or praseodymium were prepared by coprecipitation. The characteristics of all mixed oxides were tested by XRD, SEM, TEM, and XPS. XRD results showed that oxides were formed solid solution with CaF_2 structure at The particles mediun sizes (d_ (50)) of all ounces of powders were approximately 10 ~ 20 nm The area of Ce_ (0.6) Zr_ (0.3) La_ (0.04) Pr_ (0.06) O_2powder had excess 110 m ~ 2 / g after calcining at 923 K for 4 h, even calcined at 1273 K for 4 h, the area was up to 65 m ~ 2 / g.