C60 structural transformation by electrorheological testing Original Research Article

The electrorheological properties of a C60 laden silicon oil suspension was studied. Samples were prepared by dispersing C60 molecules in toluene, the solution was then incorporated into silicon oil, and finally the solvent was allowed to evaporate by heating the suspension below its boiling temperature. As prepared, C60 particles precipitated and formed small crystals. Samples were then homogenized for electrorheological testing. Electrorheological analysis showed an increase in the storage modulus as well the typical alignment of the suspension between electrodes (18/8 steel) though, the increase in storage modulus was not reversible. Fullerenes formed whiskers similar to those produced by liquid–liquid precipitation. Moreover, under a higher electric field thicker fibers were formed. C60 acts as a precursor of fibers under these circumstances. In all the cases, C60 whiskers/fibers remain after switching off the applied electric field making it a non-reversible effect, therefore not an electrorheological system.