Research output: Contribution to journal › Article › peer-review
The structure and catalytic properties of Rh-doped CeO2 catalysts. / Derevyannikova, E. A.; Kardash, T. Yu; Kibis, L. S. et al.
In: Physical Chemistry Chemical Physics, Vol. 19, No. 47, 21.12.2017, p. 31883-31897.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - The structure and catalytic properties of Rh-doped CeO2 catalysts
AU - Derevyannikova, E. A.
AU - Kardash, T. Yu
AU - Kibis, L. S.
AU - Slavinskaya, E. M.
AU - Svetlichnyi, V. A.
AU - Stonkus, O. A.
AU - Ivanova, A. S.
AU - Boronin, A. I.
N1 - Publisher Copyright: © 2017 the Owner Societies.
PY - 2017/12/21
Y1 - 2017/12/21
N2 - The average structure and the local structure of nanocrystalline Rh-doped CeO2 catalysts, prepared using a co-precipitation method, were studied using a set of structural (PDF, HRTEM, XRD) and spectral (XPS, Raman spectroscopy) methods. The samples with Rh content less than 10 wt%, calcined at 450 °C, were homogeneous solid solutions. A comparison of the experimental results and Pair distribution function (PDF) modeling data showed that Rh3+ substitutes Ce4+ ions in the fluorite phase. Charge equilibrium is obtained by the oxygen vacancy for each Rh3+ cation introduced into the ceria cell. The solid solution demonstrated high catalytic activity in low-temperature CO oxidation (LTO CO). The solid solutions were stable only in a nanocrystalline state and decomposed upon thermal treatment. The calcination of the solid solution at T > 450 °C results in a decrease in the catalytic activity that is accompanied by Rh association in the subsurface area and strong distortion of the anionic subcell. At T = 800 °C α-Rh2O3 nanoparticles are formed on the surface of the fluorite phase. The XRD-detectable Rh oxide phases are formed after calcination at 1000 °C. However, some parts of Rh within the subsurface RhxCe1-xO2-δ solid solution remain and they preserve catalytic properties for low-temperature oxidation.
AB - The average structure and the local structure of nanocrystalline Rh-doped CeO2 catalysts, prepared using a co-precipitation method, were studied using a set of structural (PDF, HRTEM, XRD) and spectral (XPS, Raman spectroscopy) methods. The samples with Rh content less than 10 wt%, calcined at 450 °C, were homogeneous solid solutions. A comparison of the experimental results and Pair distribution function (PDF) modeling data showed that Rh3+ substitutes Ce4+ ions in the fluorite phase. Charge equilibrium is obtained by the oxygen vacancy for each Rh3+ cation introduced into the ceria cell. The solid solution demonstrated high catalytic activity in low-temperature CO oxidation (LTO CO). The solid solutions were stable only in a nanocrystalline state and decomposed upon thermal treatment. The calcination of the solid solution at T > 450 °C results in a decrease in the catalytic activity that is accompanied by Rh association in the subsurface area and strong distortion of the anionic subcell. At T = 800 °C α-Rh2O3 nanoparticles are formed on the surface of the fluorite phase. The XRD-detectable Rh oxide phases are formed after calcination at 1000 °C. However, some parts of Rh within the subsurface RhxCe1-xO2-δ solid solution remain and they preserve catalytic properties for low-temperature oxidation.
KW - METAL-SUPPORT INTERACTION
KW - TEMPERATURE CO OXIDATION
KW - X-RAY
KW - ELECTRONIC INTERACTION
KW - CHEMICAL-PROPERTIES
KW - PD/CEO2 CATALYSTS
KW - RH/CEO2 CATALYST
KW - LOCAL-STRUCTURE
KW - SOLID-SOLUTION
KW - NOBLE-METALS
UR - http://www.scopus.com/inward/record.url?scp=85038353009&partnerID=8YFLogxK
U2 - 10.1039/c7cp06573f
DO - 10.1039/c7cp06573f
M3 - Article
AN - SCOPUS:85038353009
VL - 19
SP - 31883
EP - 31897
JO - Physical Chemistry Chemical Physics
JF - Physical Chemistry Chemical Physics
SN - 1463-9076
IS - 47
ER -
ID: 10065798