▎ 摘　　要

NOVELTY - Making highly-conductive graphene sheets of low oxygen content, comprises: exposing graphite powder to mixture of ammonium persulfate and sulfuric acid to produce reversible graphite intercalation compound; purging the compound with oxygen gas to provide oxygenated graphite intercalation compound; mixing the compound with piranha solution to provide piranha oxidation mixture; and subjecting the mixture to electromagnetic radiation until the graphene particles have been oxidized to the extent that highly-conductive graphene sheets of low oxygen content are obtained. USE - The process is useful for making highly-conductive graphene sheets of low oxygen content. ADVANTAGE - The process: provides highly-conductive graphene sheets of low oxygen content, where the graphene sheets have conductivity of above 7000 S/m, a carbon-to-oxygen ratio greater than 10:1 and are dispersible in various solvents without the use of special organic solvents or surfactants (claimed); is eco-friendly, rapid approach to directly produce highly-conductive and clean graphene sheets of different lateral sizes without involving any toxic regents or metal-containing compounds and without generating toxic byproducts, thus enabling a broad spectrum of applications, by solution processing techniques of low cost; relies on the synergy of piranha solution, intercalated molecular oxygen, and microwave heating that enables controlled oxidation of graphite particles, leading to rapid and direct generation of highly-conductive and clean graphene sheets; and provides scalable production of highly conductive graphene sheets from graphite particles, which can be directly and rapidly fabricated from cheap and abundant graphite particles without post separation and post reduction processing; provides graphene sheets with lower level of oxygen containing groups, which ensures outstanding electrical and optical properties; does not require high temperature annealing process; dramatically reduces waste from purification steps; and allows to reuse the byproducts to produce soil fertilizers. DETAILED DESCRIPTION - Making highly-conductive graphene sheets of low oxygen content, comprises: exposing graphite powder to a mixture of ammonium persulfate and sulfuric acid to produce a reversible graphite intercalation compound; purging the reversible graphite intercalation compound with oxygen gas to provide an oxygenated graphite intercalation compound; mixing the oxygenated graphite intercalation compound with a piranha solution to provide a piranha oxidation mixture; and subjecting the piranaha oxidation mixture to electromagnetic radiation until the graphene particles have been oxidized to the extent that highly-conductive graphene sheets of low oxygen content are obtained, where the graphene sheets are dispersible in various solvents without the use of special organic solvents or surfactants. An INDEPENDENT CLAIM is also included for highly-conductive low oxygen-containing graphene sheets produced by the process as above per se.