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…
113. Escalating ferromagnetic order via Se‐vacancy near vanadium in WSe2 monolayer
Author
Seok Joon Yun, Byeong Wook Cho, Thapa Dinesh, Dae Hee Yang, Yong In Kim, Jeong Won Jin, Sang‐Hyeok Yang, Tuan Dung Nguyen, Young‐Min Kim, Ki Kang Kim, Dinh Loc Duong*, Seong‐Gon Kim*, Young Hee Lee*
Journal
Advanced Materials
Volume(Issue)
34(10)
Page
2106551
Publication Date
2021.12.28
Abstract

Magnetic order has been proposed to arise from a variety of defects, including vacancies, antisites, and grain boundaries, which are relevant in numerous electronics and spintronics applications. Nevertheless, its magnetism remains controversial due to the lack of structural analysis. The escalation of ferromagnetism in vanadium-doped WSe2 monolayer is herein demonstrated by tailoring complex configurations of Se vacancies (SeVac) via post heat-treatment. Structural analysis of atomic defects is systematically performed using transmission electron microscopy (TEM), enabled by the monolayer nature. Temperature-dependent magnetoresistance hysteresis ensures enhanced magnetic order after high-temperature heat-treatment, consistent with magnetic domain analysis from magnetic force microscopy (MFM). The vanadium–Se vacancy pairing is a key to promoting ferromagnetism via spin-flip by electron transfer, predicted from density-functional-theory (DFT) calculations. The approach toward nanodefect engineering paves a way to overcome weak magnetic order in diluted magnetic semiconductors (DMSs) for renovating semiconductor spintronics.