Novel proficient method for isolation of endometallofullerenes from fullerene-containing soots by two-stepo-xylene–N, N-dimethylformamide extraction

Abstract

We have developed a novel proficient method of extraction of endohedral metallofullerenes from fullerene-containing soots. The method consists of two extraction steps. In the first step,o-xylene is used to extract empty fullerenes from the soot. In the second step, the same soot is extracted by polar solvent N,N-dimethylformamide. This method has been applied for isolation of endohedral La- and Y-fullerenes from the soots obtained in the electric-arc reactor. The resultant DMF extracts contain virtually no C₆₀ , C₇₀ or other empty fullerenes. The yield of the DMF extracts reaches 1% of the primary soot mass. The simple extraction method developed here enables production of large amounts of concentrated M@C_2n.