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…
141. Strain-sensitive optical properties of monolayer tungsten diselenide
Author
Hyun Jeong, Ga Hyun Cho, Jaekak Yoo, Seung Mi Lee, Rafael Salas Montiel, Hayoung Ko, Ki Kang Kim, Mun Seok Jeong*
Journal
Applied Surface Science
Volume(Issue)
653
Page
159382
Publication Date
2024.01.14
Project Number
2022R1A2C2091475
As representative layered quantum materials, monolayer (1L) transition metal dichalcogenides (TMDs) have optical and electronic properties that can be controlled by crystal strain, allowing expanded applications using strain engineering. Raman and Photoluminescence (PL) spectroscopy are the most widely used analytical tools for studying strain in 1L TMDs. Although studies have been reported on strain engineering of 1L TMDs, only results with strain greater than 0.2 % have been reported. To precisely control the strain of 1L TMDs and expand their applications, it is necessary to systematically study the changes in optical properties at low strain. This work investigated the optical property, which changes sensitively at low strains below 0.2 % of 1L TMD, using an Au honeycomb pattern template (HPT). 1L WSe2 grown by chemical vapor deposition was transferred to an Au HPT, and the strain-induced changes in optical properties were evaluated using confocal Raman and PL spectroscopy. Interestingly, Raman scattering, known to be sensitive to strain, was not changed at strains of less than 0.2 %, while the PL properties were sensitively changed at low strains in 1L WSe2. The PL properties of 1L WSe2, sensitive to strain as low as 0.2 %, have been theoretically verified by density functional theory calculations.