Asymmetric anatase TiO₂ nanocrystals with exposed high-index facets and their excellent lithium storage properties.

In this work, we demonstrate a unique organic solvent system to synthesize asymmetric anatase TiO(2) nanocrystals with a bipyramidal structure, where the upper pyramid is bound by (201) facets, and the lower pyramid is bound by (401) surfaces. Due to the high surface energy of these (401) high-index facets, the nanocrystals tend to assemble on these facets to minimize the free energy, leading to the formation of a dandelion-like hierarchical structure.