Ann: Graphene Operations Review & Capability Statement, page-61

Good morning all, I hope your all having a fantastic week,

I read back thorough the capability statement, I noticed that FGR have had there graphene tested by UoA, previously we have discussed our graphite test results that were 99.87% carbon,

FGR Graphene is 99.97% carbon, has anyone seen a better results to this ?




Comparison FGR results (green)  plotted on Talga’s results



Explanation of the RAMAN spectroscopy
The D Band
The D band is known as the disorder band or the defect band and it represents a ring breathing mode from sp2 carbon rings, although to be active the ring must be adjacent to a graphene edge or a defect. The band is typically very weak in graphite and is typically weak in high quality graphene as well. If the D band is significant it means that there are a lot of defects in the material.

The G Band
The G band is a sharp band that appears around 1587 cm-1 in the spectrum of graphene. The band is an in-plane vibrational mode involving the sp2 hybridized carbon atoms that comprises the graphene sheet. The G band position is highly sensitive to the number of layers present in the sample and is one method for determining layer thickness and is based upon the observed position of this band for a particular sample

The 2D Band
The 2D band is the second order of the D band, sometimes referred to as an overtone of the D band. It is the result of a two phonon lattice vibrational process, but unlike the D band, it does not need to be activated by proximity to a defect. As a result the 2D band is always a strong band in graphene even when there is no D band present, and it does not represent defects. This band is also used to determine graphene layer thickness.
Source : https://tools.thermofisher.com/content/sfs/brochures/AN52252_E 1111 LayerThkns_H_1.pdf