Hollow Spherical Fullerene Obtained by Kinetically Controlled Liquid-Liquid Interfacial Precipitation

Nanomaterials with hollow structures are expected to exhibit new functionalities for materials engineering. Here we report the fabrication of fullerene (C₆₀) spheres having different hollow structures by using a kinetically controlled liquid-liquid interfacial precipitation (KC-LLIP) method. For this purpose, 1,2-ethylenediamine (EDA) was used as a covalent cross-linker of C₆₀ molecules to form C₆₀-EDA shells, while in-situ generated EDA-sulfur (EDA-S) droplets were applied as ‘yolks’ being eliminated by washing following formation of the yolk-shell structure, leading to hollow structures. Porous spheres, string hollow spheres, hollow spheres, and open hollow spheres have been synthesized by controlling the kinetics of nucleation of C₆₀-EDA and the template EDA-S growth. Isopropanol was used as an additive to control the discrepancy in growth rates of C₆₀-EDA and EDA-S. This simple KC-LLIP preparation method is expected to facilitate the large-scale fabrication and application of structured C₆₀ spheres in materials science and technology.