Disclosed herein are methods for forming a graphene film on a substrate, the methods comprising depositing graphene on a surface of the substrate by a first vapor deposition step to form a discontinuous graphene crystal layer; depositing a graphene oxide layer on the discontinuous graphene crystal layer to form a composite layer; and depositing graphene on the composite layer by a second vapor deposition step, wherein the graphene oxide layer is substantially reduced to a graphene layer during the second vapor deposition step. Transparent coated substrates comprising such graphene films are also disclosed herein, wherein the graphene films have a resistance of less than about 10 KΩ/sq.