Visualizing Anisotropic Oxygen Diffusion in Ceria under Activated Conditions

Zhu, Liang; Jin, Xin; Zhang, Yu-Yang; Du, Shixuan; Liu, Lei; Rajh, Tijana; Xu, Zhi; Wang, Wenlong; Bai, Xuedong; Wen, Jianguo; Wang, Lifen

doi:10.1103/physrevlett.124.056002

DOE OSTI · 1761408

Visualizing Anisotropic Oxygen Diffusion in Ceria under Activated Conditions

Zhu, Liang·Jin, Xin·Zhang, Yu-Yang·Du, Shixuan·Liu, Lei·Rajh, Tijana·Xu, Zhi·Wang, Wenlong·Bai, Xuedong·Wen, Jianguo·Wang, Lifen

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Abstract

Oxygen reactivity plays a key role in the performance of ceria-based catalysts. Aberration-corrected transmission electron microscopy and molecular dynamics simulations were used to study the oxygen atom diffusion in ceria under activated conditions. Reactive oxygen atom and its real-time diffusion were visualized. Additionally, the interplay between cerium and oxygen atoms originating from a Coulomb interaction was revealed by the out-of-plane buckling of cerium atoms associated with oxygen transport. Anisotropic oxygen atom diffusion that depends on crystal orientations was discovered, demonstrating a preferential [001] crystallographic diffusion pathway. These findings reveal prospects for applications of anisotropic orientation-relevant fluorite-structured oxides.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY CEO2 Transmission electron microscopy XPS atomic & molecular structure atomic spectra atomic, optical & lattice clocks behavior chemical reactions energy in-situ initio molecular dynamics low-index surfaces operando

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Zhu, Liang, Jin, Xin, Zhang, Yu-Yang, Du, Shixuan, Liu, Lei, Rajh, Tijana, Xu, Zhi, Wang, Wenlong, Bai, Xuedong, Wen, Jianguo, Wang, Lifen. 2020-02-05. Visualizing Anisotropic Oxygen Diffusion in Ceria under Activated Conditions. https://doi.org/10.1103/physrevlett.124.056002

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