Partial separation of fullerenes by gradient sublimation

An experimental technique is investigated to separate/enrich fullerenes or metallofullerenes, exploiting differences in sublimation temperatures without the use of solvents. Fullerenes are sublimed out of the soot and deposited on a quartz rod along a temperature gradient (gradient sublimation). In a position-sensitive experiment the composition of the deposit on the rod is monitored by laser-desorption mass spectrometry. Strongly enriched regions containing specific fullerene molecules (i.e., C84 or La@ C82) are observed. Furthermore, C74, which could not be extracted from the soot by organic solvents, sublimes out of the soot.