A substrate-free gas-phase synthesis apparatus and method that is capable of rapidly and continuously producing graphene in ambient conditions without the use of graphite or substrates is provided. Graphene sheets are continuously synthesized in fractions of a second by sending an aerosol consisting of argon gas and liquid ethanol droplets into an atmospheric-pressure microwave-generated argon plasma field. The ethanol droplets are evaporated and dissociated in the plasma, forming graphene sheets that are collected. The apparatus can be scaled for the large-scale production of clean and highly ordered graphene and its many applications. The graphene that is produced is clean and highly ordered with few lattice imperfections and oxygen functionalities and therefore has improved characteristics over graphene produced by current methods in the art. The graphene that is produced by the apparatus and methods was shown to be particularly useful as a support substrate that enabled direct atomic resolution imaging of organic molecules and interfaces with nanoparticles at a level previously unachievable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 This invention was made with Government support under Grant Number DEI-ACO2-05CH11231 awarded by the Department of Energy (DOE) and under Grant Number NCC3-833 awarded by the National Aeronautics and Space Administration (NASA). The Government has certain rights in the invention.