A method for obtaining graphene oxide nanoplatelets and graphene nanoplatelets, said method comprising the following steps: a) dosing of at least the following compounds: i. a hydrocarbon or mixture of hydrocarbons, ii. a compound of nickel and a compound of sulphur to generate catalytic particles, iii. a carrier gas, b) placing the dosed compounds listed in step a) inside a furnace with a working temperature of between 900°C and 1500°C, where a chemical vapour deposition method occurs by the floating catalyst method, c) obtaining an intermediate material comprising carbon nanofilaments, the structure of which comprises a continuous graphite continuous ribbon where said ribbon comprises a stacking of less than eleven graphene layers spirally rolled around and along the nanofilament main axis s, d) heat treatment of the carbon nanofilaments obtained in step c) by exposing them to a temperature comprised between 1500°C and 3000°C in an inert atmosphere in order to purify, dehydrogenate, defunctionalise and crystallise said nanofilaments to a modified structure in which the number of carbon-carbon bonds is greater than the number of carbon-carbon bonds present in the carbon nanofilaments obtained in step c), e) chemical etching comprising a phase of liquid phase oxidation of the treated carbon nanofilaments from step d), causing their fragmentation, so that starting the cleaving of said graphene layers wherein, - the liquid phase oxidation is performed in a dehydrated medium, - the liquid phase oxidation of step e) is preceded by an intercalation step into the graphene layers where said intercalation is performed in an acid medium, f) completing the carbon nanofilament cleaving method by a physical method in order to obtain graphene oxide nanoplatelets with the following features: - polygonal geometry, - less than six stacked graphene layers, - a maximum length comprised between 0.1 μm and 50 μm. a) dosing of at least the following compounds: i. a hydrocarbon or mixture of hydrocarbons, ii. a compound of nickel and a compound of sulphur to generate catalytic particles, iii. a carrier gas, i. a hydrocarbon or mixture of hydrocarbons, ii. a compound of nickel and a compound of sulphur to generate catalytic particles, iii. a carrier gas, b) placing the dosed compounds listed in step a) inside a furnace with a working temperature of between 900°C and 1500°C, where a chemical vapour deposition method occurs by the floating catalyst method, c) obtaining an intermediate material comprising carbon nanofilaments, the structure of which comprises a continuous graphite continuous ribbon where said ribbon comprises a stacking of less than eleven graphene layers spirally rolled around and along the nanofilament main axis s, d) heat treatment of the carbon nanofilaments obtained in step c) by exposing them to a temperature comprised between 1500°C and 3000°C in an inert atmosphere in order to purify, dehydrogenate, defunctionalise and crystallise said nanofilaments to a modified structure in which the number of carbon-carbon bonds is greater than the number of carbon-carbon bonds present in the carbon nanofilaments obtained in step c), e) chemical etching comprising a phase of liquid phase oxidation of the treated carbon nanofilaments from step d), causing their fragmentation, so that starting the cleaving of said graphene layers wherein, - the liquid phase oxidation is performed in a dehydrated medium, - the liquid phase oxidation of step e) is preceded by an intercalation step into the graphene layers where said intercalation is performed in an acid medium, - the liquid phase oxidation is performed in a dehydrated medium, - the liquid phase oxidation of step e) is preceded by an intercalation step into the graphene layers where said intercalation is performed in an acid medium, f) completing the carbon nanofilament cleaving method by a physical method in order to obtain graphene oxide nanoplatelets with the following features: - polygonal geometry, - less than six stacked graphene layers, - a maximum length comprised between 0.1 μm and 50 μm. - polygonal geometry, - less than six stacked graphene layers, - a maximum length comprised between 0.1 μm and 50 μm.