Patent ID: 7892514

Claim:
A method of exfoliating a graphitic layered material to produce separated nano-scaled platelets having a thickness smaller than 100 nm, said method comprising: a) subjecting said graphitic layered material to a halogen vapor at a first temperature above the melting point or sublimation point of said halogen with a sufficient halogen vapor pressure and for a duration of time sufficient to cause said halogen to penetrate an interlayer space of said layered material for forming a stable halogen-intercalated layered compound having a halogen concentration of at least 5% in terms of halogen-to-layered material atomic ratio, wherein said halogen has a boiling point above 0° C. and is selected from the group consisting of bromine trifluoride (BrF 3 ), chlorine trifluoride (CIF 3 ), phosphorus trichloride (PCl 3 ), phosphorus tetrachloride (P 2 Cl 4 ), phosphorus tribromide (PBr 3 ), phosphorus triiodide (PI 3 ) and combinations thereof, or a combination of one or more thereof with diatomic halogen; and b) heating said halogen-intercalated layered compound at a second temperature above the boiling point of said halogen, allowing halogen atoms or molecules residing in the interlayer space to exfoliate said layered material to produce the platelets, wherein the platelets are obtained by step (a) and (b) without mechanical attrition of the exfoliated platelets.