Optimization Synthesis And Micro-nanostructure Of Erbium-based Endohedral Fullerenes

Fullerene is a hollow spherical molecule composed of carbon atoms.Endohedral Metal Fullerenes?EMFs?is a special compound formed by embedding metal atoms and metal clusters in the carbon cage of fullerenes.Compared with hollow fullerenes such as C₆₀ and C₇₀,EMFs have received more and more attention due to their special structure and good optoelectronic properties.Among the large families of metal fullerenes,erbium?Er?metal fullerenes are relatively rare.In this paper,the Er-EMFs was prepared by arc discharge method,and the optimized synthesis method was explored.The endohedraled Er metal fullerene was self-assembled into a micro-nano structure,showing excellent photoelectric properties.The main research contents and results are as follows:?1?Explored the use of CS₂ as solvent and repeated extraction of raw ash can significantly improve the yield of embedded Er metal fullerene.On this basis,the synthesis conditions of single component Er₃N@C₈₀ and Er₂@C₈₂ were optimized.The optimum synthesis conditions for Er₃N@C₈₀ are:Er/C molar ratio 1:9,preparation current 110A,preparation voltage 30V,furnace atmosphere 20He+3N₂?kPa?;Er₂@C₈₂ is the best synthesis condition:Er/C The molar ratio is 1:6,the preparation current is 115A,the preparation voltage is 30V,and the furnace atmosphere is 25He?kPa?;the absolute yields of Er₃N@C₈₀ and Er₂@C₈₂ are compared respectively:Er₃N@C₈₀ and the optimal synthesis conditions are prepared.The yield of Er₂@C₈₂ is 3 times and 2.6 times that under the general conditions,which greatly improves the yield of the embedded Er metal fullerene.?2?Three new types of Er-EMFs were obtained by high performance liquid chromatography multistage separation:Er₃N@I_h-C₈₀?Er₃N@D_5h-C₈₀0 and Er₂@C_s-C₈₂.The self-assembled micro-nanostructures of embedded Er metal fullerenes were prepared by liquid-liquid interface deposition?LLIP?method,and the cube morphology with smooth surface and uniform size and size of 300-400 nm was successfully obtained.In addition,the research on self-assembled micro-nanostructures of metal fullerenes is limited to Sc₃N@C₈₀,Lu₂@C₈₂,Ga@C₈₂,etc.The SEM,XRD and TEM tests on Er₃N@C₈₀ and Er₂@C₈₂nanocube structures Characterization was performed to confirm that it is a simple cubic structure in the cubic system.By measuring the light absorption properties of the cubic structure by ultraviolet spectroscopy,it is found that the absorption intensity in the visible region and the near-infrared region is greatly improved compared with the original metal fullerene,and it will have potential applications in the field of photoelectric conversion in the future.