Fabrication and Physical Properties of Novel Two-dimensional Crystal Materials Beyond Graphene: Germanene, Hafnene and PtSe2 (eBook)

This thesis reports on essential experimental work in the field of novel two-dimensional (2D) atomic crystals beyond graphene. It especially describes three new 2D crystal materials, namely germanene, hafnene, and monolayer PtSe2 fabricated experimentally for the first time, using an ultra-high vacuum molecular beam epitaxy (UHV-MBE) system.

Multiple characterization techniques, including scanning tunneling microscope (STM), low energy electron diffraction (LEED), scanning transmission electron microscope (STEM), and angle-resolved photoemission spectroscopy (ARPES), combined with theoretical studies reveal the materials' atomic and electronic structures, which allows the author to further investigate their physical properties and potential applications. In addition, a new epitaxial growth method for transition metal dichalcogenides involving direct selenization of metal supports is developed. These studies represent a significant step forward in expanding the family of 2D crystal materials and exploring their application potentials in future nanotechnology and related areas.

Linfei Li received his B.S. degree in Physics from Shandong University, China in 2008, and his Ph.D. degree in Condensed Matter Physics from the Institute of Physics, Chinese Academy of Sciences in 2015. His doctoral research project in Prof. Hongjun Gao's group focused on the fabrication and investigating the physical properties of novel two-dimensional atomic crystals beyond graphene. He then conducted postdoctoral research with Prof. Freund at the Fritz Haber Institute of the Max Planck Society in Berlin, in the course of which he primarily studied structure-catalytic activity relationships of thin oxide films grown on metal supports.

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This thesis reports on essential experimental work in the field of novel two-dimensional (2D) atomic crystals beyond graphene. It especially describes three new 2D crystal materials, namely germanene, hafnene, and monolayer PtSe2 fabricated experimentally for the first time, using an ultra-high vacuum molecular beam epitaxy (UHV-MBE) system.Multiple characterization techniques, including scanning tunneling microscope (STM), low energy electron diffraction (LEED), scanning transmission electron microscope (STEM), and angle-resolved photoemission spectroscopy (ARPES), combined with theoretical studies reveal the materials' atomic and electronic structures, which allows the author to further investigate their physical properties and potential applications. In addition, a new epitaxial growth method for transition metal dichalcogenides involving direct selenization of metal supports is developed. These studies represent a significant step forward in expanding the family of2D crystal materials and exploring their application potentials in future nanotechnology and related areas.