Defects in Functional Materials. Группа авторов

4. Summary

      In this chapter, both ADF-STEM and STM/STS demonstrate powerful atomic resolution imaging capability in the direct probing of atomic defects in 2D transition metal dichalcogendies. Point defects such as vacancy and antisite, grain/domain boundaries have been characterized by atomically resolved ADF-STEM or STM imaging, together with spectroscopy to reveal the electronic states induced by defects and low-symmetry lattice-translational stackings. Time sequential STEM to track the atomic flow also elucidate the different states involved in defects’ evolution to deduce the primary kinetic pathways in the atomic migration.

      In the 2D materials research, STEM/STM show their versatility in revealing the nanophysics of defects: both atomic characterization of the structures of defects and translational stackings and spectroscopic measurement of the electronic states induced.

       Acknowledgments

      JH and CJ acknowledge the financial support provided by the National Science Foundation of China under grant nos. 51772265, 51761165024 and 61721005, the Zhejiang Provincial Natural Science Foundation under Grant No. D19E020002, and the 111 project under no. B16042. MX acknowledges the support provided by a Collaborative Research Fund (C7036-17W) and a General Research Fund (No. 17327316) from the Research Grant Council, Hong Kong Special Administrative Region. CJ and MX also acknowledge the financial support provided by the NSFC/RGC joint research scheme (Nos. 51761165024 and N HKU732/17). The authors acknowledge Dr. Wei Huang, Feng Jiang, and Dr. Yipu Xia for their kind assistance in preparing this chapter.

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