Peking Univ, Beijing Natl Lab Mol Sci, State Key Lab Rare Earth Mat Chem & Appl, Beijing 100871, Peoples R China
; Peking Univ, PKU HKU Joint Lab Rare Earth Mat & Bioinorgan Che, Beijing 100871, Peoples R China
; Inst High Energy Phys, Beijing Synchrotron Radiat Facil, Beijing 100039, Peoples R China
Trivalent rare-earth (RE = La, Pr, Nd, Y)-doped CexZr1-xO2 (x = 0.4-0.6) solid solutions were synthesized via a urea hydrolysis-based hydrothermal method, followed by calcination at 1000 degrees C for 100 h. The X-ray absorption near-edge structure (XANES) tests for the Cc LIII edge determine that the chemical valence of the Ce atom in either undoped or RE-doped CeO2-ZrO2 samples was mainly +4. The measurements of X-ray fluorescence (XRF) and energy-filtered transmission electron microscopy (EFTEM) testify to the good compositional homogeneity for Ce, Zr, and RE atoms in both bulk and microdomain of the as-calcined CexZr1-x-yREyO2-z (x = 0.4-0.6, y = 0-0.16, and z is the number of oxygen vacancy) samples. The characterizations with X-ray diffraction (XRD) and vis-Raman demonstrate the high structural homogeneity for ternary CeO2-ZrO2-RE2O3 solid solutions after calcination at 1000 degrees C for 100 h. The aliovalent substitution of the RE3+ ion for the Ce4+ or Zr4+ ion has been concluded to stabilize the pseudo cubic t"-structure, to improve the surface area and to enhance the oxygen storage capacity (OSC) for the binary CeO2-ZrO2 system. The reducibility of the as-calcined CexZr1-x-yREyO2-z, by CO seems dependent upon the nature and concentration of the RE dopant. The highest CO-OSC value obtained in this work appeared for Ce0.5Zr0.42Nd0.08O2-z in 558 mu mol CO g(-1) at 700 degrees C, while the undoped samples gave a value of less than 460 mu mol CO g(-1).
Si, R,Zhang, YW,Wang, LM,et al. Enhanced thermal stability and oxygen storage capacity for CexZr1-xO2((x)=0.4-0.6) solid solutions by hydrothermally homogenous doping of trivalent rare earths[J]. JOURNAL OF PHYSICAL CHEMISTRY C,2007,111(2):787-794.
Si, R.,Zhang, YW.,Wang, LM.,Li, SJ.,Lin, BX.,...&吴自玉.(2007).Enhanced thermal stability and oxygen storage capacity for CexZr1-xO2((x)=0.4-0.6) solid solutions by hydrothermally homogenous doping of trivalent rare earths.JOURNAL OF PHYSICAL CHEMISTRY C,111(2),787-794.
Si, R,et al."Enhanced thermal stability and oxygen storage capacity for CexZr1-xO2((x)=0.4-0.6) solid solutions by hydrothermally homogenous doping of trivalent rare earths".JOURNAL OF PHYSICAL CHEMISTRY C 111.2(2007):787-794.