▎ 摘　　要

NOVELTY - The method comprises adding carbon source and catalyst precursor in gas inlet and outlet of quartz tube reactor, connecting the reactor in a tubular heating device, introducing inert gas to the reactor and then heating, cooling the quartz tube reactor, adding oxidant solution to obtained nitrogen-doped carbon nanotubes filled with iron and then placing in an oil bath by ultrasonic dispersion after heating and refluxing, cooling at room temperature until water is neutral, and vacuum drying. USE - The nitrogen-doped graphene nano belt is useful as anode material in a lithium battery (all claimed). ADVANTAGE - The nitrogen-doped graphene nano belt can be prepared simply in a mild reaction condition and environment friendly manner. DETAILED DESCRIPTION - The method comprises comprises (1) adding a carbon source and a catalyst precursor in a gas inlet and a gas outlet of a quartz tube reactor, where the catalyst precursor is ferric trichloride and the carbon source is nitrogen-containing solid organic compound, and mass ratio of the carbon source to the catalyst precursor is 1:0.5-5, (2) connecting the quartz tube reactor in a tubular heating device, (3) introducing inert gas to the quartz tube reactor, heating the inert gas under the presence of inert gas at reaction temperature, then passing into a middle part of the quartz tube reactor for chemical vapor deposition reaction at high temperature of 700-1000 degrees C, and stopping heating, (4) cooling the quartz tube reactor at room temperature under the protection of inert atmosphere, and collecting the product in the quartz tube reactor to obtain nitrogen-doped carbon nanotubes filled with iron, and (5) adding oxidant solution to the obtained nanotubes and then placing in an oil bath by ultrasonic dispersion after heating and refluxing at 70-140 degrees C for 0.5-18 hours, cooling at room temperature until water is neutral, and vacuum drying. An INDEPENDENT CLAIM is included for the nitrogen-doped graphene nano belt prepared from the above method.