Depletion-Induced Tunable Assembly of Complementary Platonic Solids

13/12/2024 Multicomponent self-assembly has been explored to create novel metamaterials from nanoparticles of different sizes and compositions, but the assembly of nanoparticles with complementary shapes remains rare. Recent binary assemblies were mediated by DNA base pairing or induced by solvent evaporation. Here, we introduce depletion-induced self-assembly (DISA) as a novel approach for constructing tunable binary lattices. In situ structural analysis in the real and the reciprocal spaces demonstrates DISA of a binary mixture of octahedra and tetrahedra into extended supercrystals with Fm m symmetry. The inter-particle distance, adjustable by depletant concentration, offers a versatile method for assembling nanoparticles into ordered structures while they remain dispersed in a liquid phase. We show that DISA can control the packing fraction of such binary supercrystals between φ=0.37 and φ=0.66, much lower than dense packing in the dry state. These findings highlight DISA’s potential for creating complex and highly ordered metamaterials with tailored properties. Long term collaboration with ICS (Strasbourg) and MPQ (Paris) laboratories https://doi.org/10.1021/acs.nanolett.4c04923