Controllable synthesis of star-shaped FeCoMnO x nanocrystals and their self-assembly into superlattices with low-packing densities.

We present a novel method for synthesizing monodisperse, star-shaped FeCoMnO x nanocrystals with tunable concavity. Through liquid-air interfacial assembly, these colloidal nanostars can form two-dimensional superlattices, which are characterized by low packing densities. Notably, the ability to adjust the degree of concavity of nanostars allows for the tuning of the packing symmetry of the assembled superlattices.