November 29th, 2016Objectives:

• Learn Scotch Tape Method (Mechanical Exfoliation) with ability to create TMD monolayers at will

• Master the use of Raman Microscopy to identify monolayers after deposition onto substrate

• Use AFM to gain insight into the properties of the monolayer and identify it further as a monolayer

• Use CAFM to further investigate physical properties of the monolayer with use on ITO• Apply work on composite materials for use in Bio-Optical sensors and Battery

developments

Purpose: Learn and master use of identification and characterization on chemical (physical) properties of TMD materials through the use of mechanical exfoliation, Raman microscopy, AFM and C-AFM.

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MoS2 Monolayer in contrast with the Si/SiO2 substrate

Non annealed MoS2 monolayer surface

Residue (potentially adhesive)left behind from exfoliation

Results:Flake portion characterized as monolayer, chemical (physical) properties characterization in progress, Raman gave valuable insight into the quantum yield and absorbance of the monolayer.

Discussions:The low absorbance (high transparency) of the monolayer will delay identification of the monolayer on the ITO substrate.AFM yields much information on the characteristics of the monolayer.

Conclusions:The training in mechanical exfoliation, Raman and AFM has led to easy identification of monolayers on Si/SiO2 substrates but due to the transparency of the ITO and the monolayer, identification with Raman will be difficult.