Novel Nano material Research group

Publication

Journals

  • Single-crystal growth
  • Wafer-scale single-crystal hexagonal boron nitride film via self-collimated grain formation
  • Joo Song Lee, Soo Ho Choi, Seok Joon Yun, Yong In Kim, Stephen Boandoh, Ji-Hoon Park, Bong Gyu Shin, Hayoung Ko, Seung Hee Lee, Young-Min Kim, Young Hee Lee, Ki Kang Kim, and Soo Min Kim. Science 362, 817-821 2018
  • We discover a method of synthesizing wafer-scale single-crystal (SC) hexagonal boron nitride (hBN) monolayer film. In contrary to traditional epitaxial growth, liquid gold substrate allows the self-collimation of circular hBN grains, eventually forming an SC hBN film on a wafer scale. SC hBN serves the growth template for SC-Graphene/hBN heterostructure and SC tungsten disulfide. This is the first…
  • 2D alloy
  • Tailoring Domain Morphology in Monolayer NbSe2 and WxNb1-xSe2 Heterostructure
  • ACS Nano 14, 8784-8792 2020
  • 2D material properties, including electronic and optical properties, can be adjusted through alloying. In this work, we dope NbSe2 with W to make a lateral heterostructure with semiconducting WSe2 on the inside and metallic NbSe2 on the outside. The each point of doping level is characterized by STEM (Scanning Transmission Electron Microscopy) and well correlated with optical (Raman, Photoluminesc…
  • Catalyst
  • Substitutional VSn Nanodispersed in MoS2 Film for Pt-scalable Catalyst
  • Frederick Osei-Tutu Agyapong-Fordjour, Seok Joon Yun, Hyung-Jin Kim, Wooseon Choi, Soo Ho Choi, Laud Anim Adofo, Stephen Boandoh, Yong In Kim, Soo Min Kim, Young-Min Kim, Young Hee Lee, Young-Kyu Han, and Ki Kang Kim. arXiv:2010.10908 2020
  • This work demonstrate the basal plane activation of 2D MoS2 via substituted V atoms as VSn unit in 2H-MoS2 lattice. The VSn units acts as acive sites and also charge transfer pathways for efficient hydrogen evolution.
  • Device application
  • Synthesis of hexagonal boron nitride heterostructures for 2D van der Waals electronics
  • Ki Kang Kim, Hyun Seok Lee, and Young Hee Lee. Chem. Soc. Rev. 47, 6342-6369 2018
  • This work reviews the recent progress of the large-area synthesis of hBN and other related vdW heterostructures via CVD, and artificial construction of vdW heterostructures and 2D vdW electronics based on hBN, in terms of charge fluctuations, passivation, gate dielectrics, tunneling, Coulombic interactions, and contact resistantces. The challenges and future perspectives for practical applications…
115. Identifying the Origin of Defect-Induced Raman Mode in WS2 Monolayers via Density Functional Perturbation Theory
Author
Jaekak Yoo, Kihyuk Yang, Byeong Wook Cho, Ki Kang Kim, Seong Chu Lim, Seung Mi Lee*, and Mun Seok Jeong*
Journal
JOURNAL OF PHYSICAL CHEMISTRY C
Volume(Issue)
126(8)
Page
4182–4187
Publication Date
2022.03.03
Abstract

Transition metal dichalcogenides (TMDs) are being actively studied in next-generation semiconductor applications owing to their excellent optoelectronic properties. Therefore, numerous defect-related studies have been conducted to improve TMD quality. In the study of defects, Raman spectroscopy is widely used to obtain information regarding the defects on a surface. A single sulfur-vacancy-induced Raman peak was recently reported. However, the origin of this vibrational mode has not yet been identified. Therefore, quantum mechanical calculations were performed on the sulfur-vacancy-containing supercell structure to elucidate the origin. By calculating the band structure and phonon dispersion, the phonon momentum was obtained, considering the possible scattering of electrons. After comparing the phonon momentum and phonon dispersion, it was identified that the phonon vibrational origin of a single sulfur-vacancy-induced Raman peak is A′1(k).