▎ 摘　　要

NOVELTY - Preparing graphene oxide, comprises (a) adding sodium nitrate into sulfuric acid to obtain a sodium nitrate solution in sulfuric acid, (b) adding graphite into the sodium nitrate solution in sulfuric acid to obtain expanded graphite, (c) adding potassium permanganate into the expanded graphite, in which the ratio of sodium nitrate/potassium permanganate is 0.12-0.27, to obtain a graphite suspension, and (d) adding deionized water into the graphite suspension to control the yield of graphene oxide, in which the deionized water is added at a rate of 2-8 ml/minute. USE - The method is useful for preparing graphene oxide (claimed), which is used for microstructure of transmission electron microscopy (TEM) and field-effect devices. ADVANTAGE - The method prepares the graphene oxide with high yield by controlling amount and addition rate of each component in a rapid, and safe manner. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for the amorphous graphene oxide having a layered structure, which is prepared by the above method.