Materials Research Bulletin, Vol.48, No.2, 495-503, 2013
A comparative study of SrO and BaO doping to CeO2-ZrO2: Characteristic and its catalytic performance for three-way catalysts
Ceria-zirconia-strontia (Ce0.35Zr0.55Sr0.1O1.9) and ceria-zirconia-baria (Ce0.35Zr0.55Ba0.10O1.9) were synthesized using an oxidation-co-precipitation method with hydrogen peroxide (H2O2) as oxidant. The physical and chemical properties of the prepared materials were investigated using Brunauer-Emmett-Teller surface area characterization, transmission electron microscopy, X-ray diffraction, Raman spectra, X-ray photoelectron spectroscopy, and oxygen pulse reaction. The prepared materials were used in preparing three-way catalysts with low Pt and Rh content. Moreover, catalytic activities were evaluated at a fixed bed under a simulated gaseous mixture. The results are as follows: (1) the prepared materials have a face-centered cubic structure and are nano-sized; (2) aged Ce0.35Zr0.55Sr0.10O1.9 has higher oxygen storage capacity (494 mu mol/g), better thermal stability (30 m(2)/g), good low-temperature reducibility, and high hydrogen uptake after TPR-redox cycles; (3) the light-off temperature (T-50) of Pt-Rh/CZS/LA can be as low as 199 degrees C for CO, 228 degrees C for NO, And 252 degrees C for C3H8; and (4) Pt-Rh/CZS/LA has a fairly wide working-window. (C) 2012 Elsevier Ltd. All rights reserved.