▎ 摘　　要

NOVELTY - Preparing graphene oxide involves adding graphite in the mixed liquid of strong oxidant and acid oxide to obtain closely stacked sheet acid-containing graphite oxide, where the amount of oxidant is 1-10 times of the mass of graphite, and the amount of strong acid is 10-200 times of mass of graphite. The obtained sheet graphite oxide containing acid is added in the ice water, then hydrogen peroxide is added to wash to remove excess oxidant, the reaction system is allowed to stand, the supernatant is removed, and then deionized water is added into the system. USE - Method for preparing graphene oxide (claimed). ADVANTAGE - The method enables to prepare graphene oxide which is easy to process in a simple and cost-effective manner. It has high efficiency. DETAILED DESCRIPTION - Preparing graphene oxide involves adding graphite in the mixed liquid of strong oxidant and acid oxide to obtain closely stacked sheet acid-containing graphite oxide, where the amount of oxidant is 1-10 times of the mass of graphite, and the amount of strong acid is 10-200 times of mass of graphite. The obtained sheet graphite oxide containing acid is added in the ice water, then hydrogen peroxide is added to wash to remove excess oxidant, the reaction system is allowed to stand, the supernatant is removed, and then deionized water is added into the system. The system is allowed to stand, the supernatant is removed, then deionized water is added, and the process is repeated for multiple times to obtain graphite oxide-free acid. The graphite oxide-free acid is added with treating agent by shaking, ground by sand grinding and ball milling, ultrasound or cut, and processed in different sized to obtain oxidized graphene dispersion liquid. The graphene oxide dispersion is subjected to spray drying, freeze drying or supercritical fluid drying to obtain graphene oxide powder.