▎ 摘　　要

NOVELTY - Preparing a binary transition metal oxide and graphene oxide composite material involves: (1) mixing a dispersion liquid containing a transition metal compound (A) with graphene oxide to obtain a product (A); (2) adding a transition metal compound (B) to the product (A) to carry out hydrothermal reaction, and freeze drying to obtain a product (B); and (3) calcining the product (B). The product (B) includes graphene oxide and a Prussian blue analog, which is grown in situ on the graphene oxide. USE - The method is useful for preparing a binary transition metal oxide and graphene oxide composite material, which is useful in a sodium-ion battery (claimed). ADVANTAGE - The Prussian blue analog in the preparation method is grown in situ on the surface of the graphene oxide, so that the Prussian blue analog is more tightly combined with graphene oxide, and the battery is more stable during charge and discharge process, thus improving the electrochemical performance of the graphene oxide composite material. The graphene oxide is subjected to the hydrothermal reaction to obtain three-dimensional graphene oxide, which increases the specific surface area of the composite material, effectively alleviates the volume expansion of the binary transition metal oxide, effectively prevents agglomeration of the binary transition metal oxide and improves the electrical conductivity and cycle performance of the composite material. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) the binary transition metal oxide and graphene oxide composite material obtained by the above preparation method; and (2) a sodium-ion battery, which comprises a positive electrode and a negative electrode, where the material of the negative electrode is the binary transition metal oxide and graphene oxide composite material.