A Copper-based Supramolecular Nanocapsule that Enables Straightforward Purification of Sc3N-based Endohedral Metallofullerene Soots

Abstract

A self-assembled Cu II -based nanocapsule enables efficient and straightforward isolation of Sc 3 N@C 80 from arc-processed raw soot. The newly designed Cu II -based supramolecular nanocapsule 5⋅(OTf) 8 was used to effectively entrap fullerenes and endohedral metallofullerenes (EMFs) with different affinities depending on their size and shape. Moreover, we took advantage of the sharply different entrapment abilities of the 5⋅(OTf) 8 cage in the solid state versus in solution to encapsulate all the species with the exception of Sc 3 N@C 80 (both I h and D 5h isomers), which remains pure in solution. HPLC quantification determined that up to 85 % of the total Sc 3 N@C 80 content in the initial mixture was recovered in very high purity ( > 99.5 %). The complete release of the encapsulated species with an orthogonal solvent-washing strategy regenerates 5⋅(OTf) 8 ready to be re-used. This approach opens new opportunities for EMFs purification