more graphitic behavior has more IG than defects which belong to ID ....

so IG/ID is more for Pure graphene .... hence you can know wether small or large flakes are more pure ( defect free)

How did you obtain the graphene flakes? If by exfoliation of graphene oxide, followed by reduction, then you will find that chemical reduction crumbles the edges of the reduced graphene oxide. Representation of surface in the edges around the borders will be more frequent for smaller flakes.

can u further attach the complete Raman spectra for e.g. 3 sizes?

Hello Md.Akibul Islam ,

First of all I´m so happy to find someone with the same interrogations and tell you that the graph you post it has great meaning, so if you permit me to give you my point of view take it, and construe as you consider.

Larger nanoplatelets tend to stabilize ans show more of their inner vacancy defects (something like grain boundaries) nor the edge defects. But smallers graphene nanoplatelets show more edge defects, even that ratio could be very useful to determine the size at witch you can obtain more oriented nanoplatelets.

I´d be attentive, bests