The G and 2D Raman peaks of n-layer graphenes show upshifts after treatment by these two kinds of plasma, indicating p-doping. Under the same experimental conditions, D, D’ and D+G peaks can clearly be observed for monolayer graphene, whereas these peaks are absent for thicker n-layer graphenes (n≥2), which indicates that the fluorination of monolayer graphene is more feasible than for thicker graphenes.

Comparison of I(2D)/I(G) and I(D)/I(G) of CHF3/CF4 plasma-treated graphenes indicates that CF4 plasma treatment introduces more p-doping and less defects. Meanwhile, the fluorination of monolayer graphenes by CF4 plasma is reversible through thermal annealing whereas the CHF3 plasma treatment is irreversible.

Applications for fluorinated graphene include electronic devices and hybrid materials.

The researchers presented the work in the journal Nanotechnology.