Assembly of Janus fullerenol: a novel approach to prepare rich carbon structures

C60(OH)8 is a fullerenol with all the hydroxyl groups located in the same hemisphere. It combines the fascinating assembly behaviour of a Janus particle and the unique properties of a fullerene. Since the range of interparticle hydrophobic attraction in water is much longer than the particle size, C60(OH)8 has a strong tendency to form aggregates. At concentrations above 1.0 × 10−6 M, the Rg of the aggregate is 110 nm and the aggregation number reaches 2.5 × 105. However, the conformation of the aggregate is not condensed, C60(OH)8 can still adjust its position by transportation or rotation. Therefore, when deposited on the surface, C60(OH)8 assembles into a spherical structure or a single-layered fiber on the hydrophilic surface, but it forms a toroidal structure with concentric rings on the hydrophobic surface. If illuminated with light during assembly, fibers composed of multi-braids are observed on the hydrophilic surface. Our work demonstrated that the assembly of Janus fullerenol offered a new approach to prepare novel carbon structures.