▎ 摘　　要

Intercalation doping has been theoretically and experimentally studied on chemical vapor deposition synthesized few-layer graphene. Density functional theory calculations identified FeCl3 as a good dopant to reduce the sheet resistance of few-layer graphene. A simple vapor transfer method is employed to dope graphene. The successful doping is confirmed by the Raman spectra as well as the electrical measurements. After doping, graphene shows p-type conducting behavior and its conductance is significantly enhanced compared with that of undoped graphene. Three-layer graphene exhibited a sheet resistance of 40 Omega/square, while four-layer doped graphene has even smaller sheet resistance of 20 Omega/square, with transmittance >= 90% for both cases, which provide the best combination of sheet resistance and transmittance among all previously reported transparent conductors.