▎ 摘　　要

NOVELTY - The method for preparing metal oxide two-dimensional material involves dissolving metal salt in solvent such that the metal in the solution is in an ionic state, adding graphene oxide, stirring to adsorb metal ions, centrifuging, washing to obtain adsorbed graphene oxide, dispersing in deionized water to obtain dispersion, quickly freezing the ice, placing the ice cubes in freeze dryer to remove moisture, obtaining adsorbed metal ions of graphene oxide in a dry state, degassing in the air to remove graphene oxide to obtain metal oxide two-dimensional material. USE - Method for preparing two-dimensional material of metal oxide e.g. calcium oxide for biodiesel preparation, electrocatalysis application, photocatalytic application, photodegradation application, gas catalysis application, lithium ion battery and gas-sensitive application (all claimed). ADVANTAGE - The environmentally-friendly method enables preparation of metal oxide two-dimensional material by simple process. DETAILED DESCRIPTION - Method for preparing metal oxide two-dimensional material involves dissolving metal salt in solvent such that the metal in the solution is in an ionic state, adding graphene oxide, stirring to adsorb metal ions, centrifuging, washing to obtain adsorbed graphene oxide, dispersing in deionized water to obtain dispersion, quickly freezing the ice into the dispersion using ultrafast freezing process, placing the ice cubes in freeze dryer to remove moisture, obtaining adsorbed metal ions of graphene oxide in a dry state, degassing in the air to remove graphene oxide to obtain metal oxide two-dimensional material.