title: Aluminum-doped ceria-zirconia solid solutions with enhanced thermal stability and high oxygen storage capacity.
abstract: A facile solvothermal method to synthesize aluminum-doped ceria-zirconia (Ce0.5Zr0.5-xAlxO2-x/2, x = 0.1 to 0.4) solid solutions was carried out using Ce(NH4)2(NO3)6, Zr(NO3)3·2H2O Al(NO3)3·9H2O, and NH4OH as the starting materials at 200°C for 24 h. The obtained solid solutions from the solvothermal reaction were calcined at 1,000°C for 20 h in air atmosphere to evaluate the thermal stability. The synthesized Ce0.5Zr0.3Al0.2O1.9 particle was characterized for the oxygen storage capacity (OSC) in automotive catalysis. For the characterization, X-ray diffraction, transmission electron microscopy, and the Brunauer-Emmet-Teller (BET) technique were employed. The OSC values of all samples were measured at 600°C using thermogravimetric-differential thermal analysis. Ce0.5Zr0.3Al0.2O1.9 solid solutions calcined at 1,000°C for 20 h with a BET surface area of 18 m2 g-1 exhibited a considerably high OSC of 427 μmol-O g-1 and good OSC performance stability. The same synthesis route was employed for the preparation of the CeO2 and Ce0.5Zr0.5O2. The incorporation of aluminum ion in the lattice of ceria-based catalyst greatly enhanced the thermal stability and OSC.
authors.affiliation: Center for Exploration of New Inorganic Materials (CENIM), Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan. shuyin@tagen.tohoku.ac.jp.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Dong
authors.forename: Shu
authors.initials: S
authors.lastname: Yin
authors.forename: Chongshen
authors.initials: C
authors.lastname: Guo
authors.forename: Tsugio
authors.initials: T
authors.lastname: Sato