High Thermal Stability of La2O3- and CeO2-Stabilized Tetragonal ZrO2

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• 作者：Shichao Wang ; Hong Xie ; Yuyuan Lin ; Kenneth R. Poeppelmeier ; Tao Li ; Randall E. Winans ; Yanran Cui ; Fabio H. Ribeiro ; Christian P. Canlas ; Jeffrey W. Elam ; Hongbo Zhang ; Christopher L. Marshall
• 刊名：Inorganic Chemistry
• 出版年：2016
• 出版时间：March 7, 2016
• 年：2016
• 卷：55
• 期：5
• 页码：2413-2420
• 全文大小：572K
• ISSN：1520-510X

文摘

Catalyst support materials of tetragonal ZrO₂, stabilized by either La₂O₃ (La₂O₃–ZrO₂) or CeO₂ (CeO₂–ZrO₂), were synthesized under hydrothermal conditions at 200 °C with NH₄OH or tetramethylammonium hydroxide as the mineralizer. From in situ synchrotron powder X-ray diffraction and small-angle X-ray scattering measurements, the calcined La₂O₃–ZrO₂ and CeO₂–ZrO₂ supports were nonporous nanocrystallites that exhibited rectangular shapes with a thermal stability of up to 1000 °C in air. These supports had an average size of ∼10 nm and a surface area of 59–97 m²/g. The catalysts Pt/La₂O₃–ZrO₂ and Pt/CeO₂–ZrO₂ were prepared by using atomic layer deposition with varying Pt loadings from 6.3 to 12.4 wt %. Monodispersed Pt nanoparticles of ∼3 nm were obtained for these catalysts. The incorporation of La₂O₃ and CeO₂ into the t-ZrO₂ structure did not affect the nature of the active sites for the Pt/ZrO₂ catalysts for the water–gas shift reaction.