NOVELTY - Producing reduced graphene oxide, comprises: (a) providing a dispersion of graphene oxide in an aqueous medium comprising water and at least one reducing agent precursor compound, which is irradiated using an electron beam radiation or radiation with UV radiation having a wavelength of 200-320 nm, or radiation with visible light reducing radical species; and (b) radiating the dispersion with an electron beam or UV/VIS-radiation, preferably having a wavelength of 200-320 nm.    USE - The method is useful for producing reduced graphene oxide, which is useful as an electrode material for batteries or double layer capacitors, electrically conductive coatings in electronic and opto-electronic components and sensors, a material for electromagnetic shielding or a component of polymer materials and nanocomposites, in conductive inks, solar cells, fuel cells, energy storage materials and applications in telecommunications and biotechnology (all claimed).    ADVANTAGE - The method enables economical production of the reduced graphene oxide with high purity, mechanical strength, and thermal and electric conductivity.    DETAILED DESCRIPTION - Producing reduced graphene oxide, comprises: (a) providing a dispersion of graphene oxide in an aqueous medium comprising water and at least one reducing agent precursor compound, which is irradiated using an electron beam radiation or radiation with UV-radiation having a wavelength of 200-320 nm, or radiation with visible light reducing radical species; and (b) radiating the dispersion with an electron beam or UV/visible-radiation having a wavelength of 200-320 nm, where the graphene oxide is converted by the formed reducing radical species during the radiation into the reduced graphene oxide. INDEPENDENT CLAIMS are included for:    (1) the reduced graphene obtained by the method, where the reduced graphene has carbon/oxygen ratio of at least 10, preferably less than 13 and/or a surface resistivity of more than 104 to 105 Omega /square, with the exception of oxygen and hydrogen atoms, free from built impurity atoms, which originate from the reducing agents; and    (2) the aqueous solution containing the reduced graphene oxide, where the solution is stable for several months and is obtained by the method.