Van der Waals epitaxial growth of single crystal α-MoO3 layers on layered materials growth templates

Jong Hun Kim, Jatis Kumar Dash, Junyoung Kwon, Changbae Hyun, Hangyel Kim, Eunji Ji, Gwan Hyoung Lee

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Since the isolation of graphene, various two-dimensional (2D) materials have been extensively investigated. Nevertheless, only few 2D oxides have been reported to date due to difficulties in their synthesis. However, it is expected that the layered transition-metal oxides (TMOs) could be missing blocks for van der Waals heterostructures and essential elements for 2D electronics. Herein, the crystal structure and band structure of van der Waals epitaxially grown α-MoO3 nanosheets on various 2D growth templates are characterized. Monolayer and multilayer α-MoO3 nanosheets are successfully grown on a 2D substrate by simply evaporating amorphous molybdenum oxide thin film in ambient conditions. A single-crystal α-MoO3 nanosheet without grain boundary is epitaxially grown on various 2D substrates despite a large lattice mismatch. During growth, the quasi-stable monolayer α-MoO3 first covers the 2D substrate, then additional layers are continuously grown on the first monolayer α-MoO3. The band gap of the α-MoO3 increases from 2.9 to 3.2 eV as the thickness decreases. Furthermore, due to oxygen vacancies and surface adsorbates, the synthesized α-MoO3 is highly n-doped with a small work function. Therefore, α-MoO3 field-effect transistors (FETs) exhibit a typical n-type conductance. This work shows the great potential of ultra-thin α-MoO3 in 2D-material-based electronics.

Original languageEnglish
Article number015016
Journal2D Materials
Volume6
Issue number1
DOIs
Publication statusPublished - 2019 Jan

Fingerprint

Nanosheets
Epitaxial growth
Monolayers
templates
Single crystals
single crystals
Electronic equipment
Substrates
Molybdenum oxide
molybdenum oxides
Lattice mismatch
Oxides
Oxygen vacancies
Adsorbates
Field effect transistors
electronics
Band structure
Graphene
Oxide films
Transition metals

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Cite this

Kim, J. H., Dash, J. K., Kwon, J., Hyun, C., Kim, H., Ji, E., & Lee, G. H. (2019). Van der Waals epitaxial growth of single crystal α-MoO3 layers on layered materials growth templates. 2D Materials, 6(1), [015016]. https://doi.org/10.1088/2053-1583/aaedc8
Kim, Jong Hun ; Dash, Jatis Kumar ; Kwon, Junyoung ; Hyun, Changbae ; Kim, Hangyel ; Ji, Eunji ; Lee, Gwan Hyoung. / Van der Waals epitaxial growth of single crystal α-MoO3 layers on layered materials growth templates. In: 2D Materials. 2019 ; Vol. 6, No. 1.
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Van der Waals epitaxial growth of single crystal α-MoO3 layers on layered materials growth templates. / Kim, Jong Hun; Dash, Jatis Kumar; Kwon, Junyoung; Hyun, Changbae; Kim, Hangyel; Ji, Eunji; Lee, Gwan Hyoung.

In: 2D Materials, Vol. 6, No. 1, 015016, 01.2019.

Research output: Contribution to journalArticle

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