Flame-annealing assisted synthesis of graphene films from adamantane

Here we demonstrate a facile approach to grow uniform and large area single layer graphene directly over polycrystalline metal foil from nanoporous carbon (NC) material. The NC is synthesized by using the adamantane (C ₁₀H₁₆) flame method. The flame-annealing of adamantane resulted in the conversion of adamantane to NC. The size of NC is ∼80 to 100 nm. The prepared sandwich structures (Mo-NC-Ni-dielectric-Mo) were annealed at 850 to 950 °C, where NC was used as a carbon source material. The NC material was successfully transformed into single layer graphene. We have explored the possibility of using our approach to grow graphene in low vacuum (1 × 10^-10 Pa) air instead of inert Ar atmosphere. The generated pressure on sandwich structures has enhanced the density/scalability as well as the quality of graphene. We observed the sheet resistance of graphene was ∼929 Ω per sq at 91.8% transparency. Our work expands the possibility of synthesizing single-layer graphene from various carbon source materials. Moreover, the synthesized graphene films can be applied for future electronics applications.