The invention belongs to the technical field of nano-materials, and relates to a preparation method of a magnetic
metal or
alloy film with a nano-structure. The preparation method of the film comprises the following steps: (1) a reaction solution preparation: dissolving a magnetic
metal salt in
distilled water, adding an organic complexing agent, a strong base, a
reducing agent and alcohols into the solution and stirring to form a clear and transparent solution, wherein the organic complexing agent contains at least one of amino, carboxyl and hydroxyl; and the alcohols with a
boiling point lower than that of water are capable of mixing and dissolving with water; and (2) tightly pressing a substrate film on the inner wall of a reaction container, transferring the prepared reaction solution in the reactor, sealing the reactor and placing the reactor at the central part of an annular column-shaped
magnet, and heating the reaction container to carry out the reaction, wherein the reduced
metal or
alloy nano-particles are migrated to the substrate film under the effect of a
magnetic field and deposited on the film, then the magnetic metal or
alloy film with the nano-structure is prepared. The preparation method is low in cost, simple in device and technical condition, cheap in
reagent and applicable for production on a large scale.