Study of the Phase Transformation of Single Particles of Ga2O3 by UV-Raman Spectroscopy and High-Resolution TEM

Authors

  • Xiang Wang,

    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    2. Graduate University of Chinese Academy of Sciences, Chinese Academy of Sciences, No.19A Yuquan Road Beijing, 100049 (P. R. China)
    Search for more papers by this author
  • Dr. Qian Xu,

    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    Search for more papers by this author
  • Dr. Fengtao Fan,

    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    Search for more papers by this author
  • Dr. Xiuli Wang,

    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    Search for more papers by this author
  • Dr. Mingrun Li,

    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    Search for more papers by this author
  • Prof. Zhaochi Feng,

    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    Search for more papers by this author
  • Prof. Can Li

    Corresponding author
    1. State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447
    • State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian National Laboratory for Clean Energy, 457 Zhongshan Road, Dalian 116023 (P. R. China), Fax: (+86)-411-84694447

    Search for more papers by this author

Abstract

By taking advantage of UV-Raman spectroscopy and high-resolution TEM (HRTEM), combined with the focused ion beam (FIB) technique, the transformation from GaOOH into α-Ga2O3 and then into β-Ga2O3 was followed. We found that the stepwise transformations took place from the surface region before developing into the bulk of single particles without particle agglomeration and growth. During the transformation from GaOOH into α-Ga2O3, the elimination of water vapor through the dehydroxylation of GaOOH resulted in the formation of micropores in the single particles, whilst maintaining their particle size. For the phase transformation from α-Ga2O3 into β-Ga2O3, the nucleation of β-Ga2O3 was found to occur at the surface defects and this process could be retarded by occupying these defects with a small amount of La2O3. By finely controlling the process of the phase transformation, the β-Ga2O3 domains gradually developed from the surface into the bulk of the single particles without particle agglomeration. Therefore, the surface structure of the α-Ga2O3 single particles can be easily tuned and a particle with an α@β core–shell phase structure has been obtained.

Abstract

Thumbnail image of

Ancillary