▎ 摘　　要

NOVELTY - Molecular assembly method involves: (1) ultrasonically dispersing a substrate in a sodium oleate solution; (2) slowly adding a metal ion solution to the solution obtained in step (1), precipitating, and washing with water; and (3) drying the precipitate obtained in step (2) at 80degrees Celsius, and pyrolyzing at high temperature by carbonizing at 400-500degrees Celsius for 2-4 hours under nitrogen atmosphere. The substrate is graphene oxide, silicon dioxide microspheres, carbon tube, carbon fiber or silicon wafer. The metal ion solution comprises ferric chloride, cobalt chloride, manganese chloride, nickel chloride and/or chromium chloride. USE - Molecular assembly method for in-situ synthesis of monolayer nanocrystals used in magnetic, electrochemical, optical and biomedical applications. ADVANTAGE - The method can assemble a layer of nanocrystal on substrates, ensures adjustable components and high coverage, and overcomes the problem that the existing method can load single particle on a single substrate, the loading amount is low, and the agglomeration is inevitable.