The effect of solvent ratio and water on the growth of C60 nanowhiskers

The growth of C60 nanowhiskers (C60NWs) prepared by a modified liquid–liquid interfacial precipitation method is investigated, focusing on the effect of solvent ratio and water content in the C60–toluene–isopropyl alcohol (IPA) solution system. The precipitation of C60NWs was markedly influenced by the solvent ratio of toluene to IPA, and the C60NWs were found to grow longer above a critical diameter (Dc), which depends on the solvent ratio. The addition of a small amount of H2O to the C60–toluene–IPA solution promoted the growth of C60NWs. This catalytic effect of water on the growth of C60NWs was confirmed also by the experiment using heavy water (D2O) and by the decrease of growth activation energy of C60NWs with increase of H2O content in the C60–toluene–IPA solution.