Yes absolutely ! Of course you need to use a metallic tip and a metallic substrate to close the circuit. see for example Article Local conductance measurement of graphene layer using conduc...

Also you can directly probe the moire effect when G is exfoliated on Boron nitride https://arxiv.org/pdf/1401.2637.pdf

Thank you Sir.

Dear Md.Akibul Islam,

Yes, it is possible to probe the conductivity of exfoliated graphene using scanning probe microscopy (i.e. cAFM).

Attached herewith Research Article links which will help you:

01. Conference Paper Nanoscale electrical mapping of two-dimensional materials by...

02. http://dspace.unict.it/bitstream/10761/91/1/Thesis_manuscript_Sushant_Sonde_ArchivIA.pdf

03. http://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=1168&context=nanopub

04. https://duepublico.uni-duisburg-essen.de/servlets/DerivateServlet/Derivate-43543/Alvarado_Diss.pdf

05. http://pubs.acs.org/doi/full/10.1021/nn400557b?src=recsys

06. https://worldwidescience.org/topicpages/s/scanning+probe+oxidation.html

I hope the information will help you.

With Best Wishes,

Samir G. Pandya

Yes, but please remember that the contact resistance between the C-AFM tip and the sample and probably also the resistance of the set-up (tip+cable) are also measured because C-AFM is actually a two-contact electrical measurement. As a result, I think that while a comparison in term of conductivity can be done (assuming that the tip-sample contact is the same and the same tip is used), the measured value should not be claimed as the absolute value of the conductivity of the measured sample (unless a performed measurement is more elaborated than just scanning a C-AFM tip).