Iodine doping in solid precursor-based CVD growth graphene film

Doping of different elements in intrinsic graphene is of great importance to adjust the electrical and chemical properties for realization of different electronic devices. Here, we demonstrate a simple and controllable synthesis process of iodine-doped graphene film using camphor (C10H16O), a solid botanical derivative. In situ doping of iodine in a graphene film has many difficulties in a conventional chemical vapor deposition process using a gas source. In this technique, iodine was mixed with the carbon precursor and simultaneously evaporated to pyrolysis on a metal catalytic substrate. Raman and X-ray photoelectron spectroscopic studies confirm the presence of elemental iodine in the form of triiodide and pentaiodide. Simultaneously, evaporated iodine atoms remains within the few-layers graphene structure and interact with carbon atoms through a charge transfer process. This shows a straightforward technique for iodine doping in graphene and a similar approach can be adopted to deposit iodine-doped graphene on other metal substrates.