THE sCOTCH-TAPE METHODThis method was popularized in 2004 when Andre Geim and Konstantin Novoselov, both of the University of Manchester in England, discovered they could make atomically thin layers of carbon by repeatedly cleaving graphite with adhesive tape and this eventually won them the Nobel Prize in Physics in 2010.
Despite its complicated name, the Scotch-tape based micromechanical exfoliation method essentially just involves the use of repeated peeling of a Molybdenum Disulfide crystal using adhesive tape until a single layer of MoS2 is obtained. |
The video shows the scotch-tape based micromechanical exfoliation method for Graphene. The method is done the in same way for MoS2.
The main advantage of the Scotch-tape method is its simplicity. Yet at the same time, this method might seem crude at times, yielding combinations of mono-layered, double-layered and multi-layered MoS2 on the same piece of tape at the same time. In 2D materials, the number layers of the materials is the determining factor of the properties possessed and hence it is necessary for scientists to ensure that the sample being analysed is indeed a monolayer material. The most common way of doing so is through Raman Spectrometry.
Raman Spectrometry
Raman Spectrometry
References:
[1] Matson, J. (2014). Graphene Researchers Geim and Novoselov Win Nobel Prize in Physics [Updated].Scientificamerican.com. Retrieved 9 September 2014, from http://www.scientificamerican.com/article/geim-novoselov-physics-novel/
[2] Dai, M., Kvashnin, D., Sorokin, P., Najmaei, S., Ajayan, P., & Yakobson, B. et al. (2014). Nanomechanical cleavage of molybdenum disulphide atomic layers. Nature Communications, 5. doi:10.1038/ncomms4631
[3]
[1] Matson, J. (2014). Graphene Researchers Geim and Novoselov Win Nobel Prize in Physics [Updated].Scientificamerican.com. Retrieved 9 September 2014, from http://www.scientificamerican.com/article/geim-novoselov-physics-novel/
[2] Dai, M., Kvashnin, D., Sorokin, P., Najmaei, S., Ajayan, P., & Yakobson, B. et al. (2014). Nanomechanical cleavage of molybdenum disulphide atomic layers. Nature Communications, 5. doi:10.1038/ncomms4631
[3]