The invention provides a high-entropy single-
crystal metal oxide with a cation disordered salt
rock structure and a preparation method and application thereof. The preparation method of the
metal oxide comprises the following steps of: mixing at least five
transition metal compounds and
lithium source
powder, and carrying out ball milling to obtain a precursor; fully mixing the precursor with fused salt, tabletting,
sintering at high temperature in an
inert atmosphere, and rapidly cooling to obtain a product; and separating the product, washing the product with a
solvent, and
drying the product to obtain the high-entropy single-
crystal metal oxide with a cation disordered rock salt structure. The
transition metal compounds comprise at least one compound selected from Mo < 6 + >, V < 5 + >, Nb < 5 + > and Ti < 4 + >. The metal oxide obtained by the preparation method provided by the invention is a sphere-like
single crystal, is of an Fm-3m type structure, is used as a secondary battery positive
electrode material, and shows relatively
high energy density and good
cycling stability.