In Situ Resolving the Atomic Reconstruction of SnO2 (110) Surface

Guanxing Li; Songda Li; Zhong-Kang Han; Chen Zou; Hanglong Wu; Wentao Yuan; Beien Zhu; Yi Gao; Hangsheng Yang; Ze Zhang; Yong Wang

doi:10.1021/acs.nanolett.1c02501

In Situ Resolving the Atomic Reconstruction of SnO₂ (110) Surface

Nano Lett. 2021 Sep 8;21(17):7309-7316. doi: 10.1021/acs.nanolett.1c02501. Epub 2021 Aug 19.

Authors

Guanxing Li¹, Songda Li¹, Zhong-Kang Han², Chen Zou¹, Hanglong Wu¹, Wentao Yuan¹, Beien Zhu^{3

4}, Yi Gao^{3

4}, Hangsheng Yang¹, Ze Zhang¹, Yong Wang¹

Affiliations

¹ Center of Electron Microscopy and State Key Laboratory of Silicon Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
² Center for Energy Science and Technology, Skolkovo Institute of Science and Technology, Moscow 413026, Russia.
³ Division of Interfacial Water and Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China.
⁴ Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201210, China.

PMID: 34410724
DOI: 10.1021/acs.nanolett.1c02501

Abstract

Understanding surface reconstruction of nanocrystals is of great importance to their applications, however it is still challenging due to lack of atomic-level structural information under reconstruction conditions. Herein, through in situ spherical aberration corrected scanning transmission electron microscopy (STEM), the reconstruction of nanocrystalline SnO₂ (110) surface was studied. By identifying the precise arrangements of surface/subsurface Sn and O columns through both in situ bright-field and high-angle annular dark-field STEM images, an unexpected added Sn₂O model was determined for SnO₂ (110)-(1 × 2) surface. The protruded Sn^δ+ of this surface could act as the active sites for activating O₂ molecules according to our density functional theory (DFT) calculations. On the basis of in situ observation of atomic-level reconstruction behaviors and DFT calculations, an energy-driven reconstruction process was also revealed. We anticipate this work would help to clarify the long-standing debate regarding the reconstruction of SnO₂ (110) surface and its intrinsic property.

Keywords: SnO2 (110) surface; in situ scanning transmission electron microscopy; oxide nanocrystal; structure−property relationship; surface reconstruction.