Major Research Result

NEW As Thin as it Gets: Peeling off Atomically Thin Graphene from Natural Graphite

  • 2021-02-08
  • 7441

A breakthrough in 2D graphene fabrication paves the way for its large-scale production 



Graphene is a promising pure carbon 2D material that can revolutionize electronics. However, it is difficult to produce high-quality large-area graphene films. Now, scientists from Korea have developed a novel method to peel off uniform and atomically thin layers of graphene from a natural graphite crystal, paving the way for large-scale production. 

 


Graphene is a promising nanomaterial that could lead to tremendous advances in electronics, including bendable and wearable devices, faster transistors, and new semiconductors  

Photo courtesy: Shutterstock 

Graphene is a solid made purely from carbon atoms arranged in a 2D honeycomb-like structure. Its unique mechanical, chemical, electric, and optical properties have made it a hot topic in materials science; the next generation of electronics like faster transistors, wearable and bendable phones and other electronics can very well be based on graphene. Unfortunately, there are still no efficient ways to produce large-area graphene films with a thickness of a few atoms. If graphene is to revolutionize upcoming technology, a better fabrication technique is a must. 


That’s why a team of scientists from Korea, led by Associate Professor Jae-Hyun Lee from Ajou University, recently published a study in Science Advances in which they pioneer a promising strategy to produce atomically thin graphene films. Instead of going for a chemical route, they focused on developing a new method for the exfoliation—or peeling off—of graphene out of a natural graphite crystal. 


Traditional exfoliation methods involve removing thin layers of graphene from graphite using special adhesive tapes. However, this only yields pieces of graphene a few micrometers across. In the new strategy the scientists developed, a thin metallic film is first deposited on a large graphite crystal and then removed, lifting along a graphene film from the crystal. The key to this method is that the metallic film attracts carbon atoms in the top few layers with a slightly higher binding energy than carbon atoms in deeper layers. What’s more, different metals can yield large graphene layers with a uniform thickness of one, two, or three carbon atoms. 


We studied the mechanisms by which cracks form when graphene is exfoliated and found a way to control them in size and direction at an atomic scale,” remarks Dr. Lee, “The area and density of the atomically thin graphene layers we extracted were respectively 4,200 and 6,000 times larger compared with existing exfoliation methods.”        


This study could solve the long-standing issue of producing high quality graphene films with high yield and large area, which has been an obstacle to the research and commercialization of graphene-based technology. Excited about the results, Dr. Lee concludes, “Graphene may bring forth a new generation of electronics, including faster transistors and even wearable and bendable phones. Our exfoliation technique paves the way for developing manufacturing process for the mass production of graphene and other 2D materials.” 


With any luck, refining this technique could set us on the course for a technological revolution! 



Reference

Authors:

Ji-Yun Moon1, Minsoo Kim2, Seung-Il Kim1, Shuigang Xu2, Jun-Hui Choi3, Dongmok Whang4, Kenji Watanabe5, Takashi Taniguchi6, Dong Seop Park7, Juyeon Seo7, Sung Ho Cho7,*, Seok-Kyun Son3,* and Jae-Hyun Lee1,*

Title of original paper:

Layer-engineered large-area exfoliation of graphene

Journal:

Science Advances

DOI:

10.1126/sciadv.abc6601

Affiliations:

1Department of Energy Systems Research and Department of Materials Science and Engineering, Ajou University

2School of Physics and Astronomy, University of Manchester

3Department of Physics, Mokpo National University

4School of Advanced Materials Science and Engineering, Sungkyunkwan University

5Research Center for Functional Materials, National Institute for Materials Science

6International Center for Materials Nanoarchitectonics, National Institute for Materials Science

7Mobile Display Process Architecture, Samsung Display



*Corresponding authors’ emails: jaehyunlee@ajou.ac.kr (J.-H.L.)


About Ajou University

Founded in 1973, Ajou University has quickly grown to become one of the top universities in the Republic of Korea. With over 15,000 students and 50 research centers in diverse fields, Ajou University partakes in the largest national research and graduate education project funded by the Korean Ministry of Education. In line with its recently reformed vision, Ajou University’s goal is to change society by connecting minds and carrying out high-impact research to improve the welfare of people in and outside Korea. 


Website: https://www.ajou.ac.kr/en/index.do 



About the author

Dr. Jae-Hyun Lee is an Associate Professor at the Department of Energy Systems and Engineering at Ajou University, Korea. His group explores and develops new physics and phenomena using advanced two-dimensional (2D) materials. The particular speciality of his group is the mesoscopic investigation of new types of van der Waals (vdW) heterostructures, including carbon nanotubes, 2D materials, and nanowires.