Self-Assembly of Nanoparticles into Biomimetic Capsid-like Nanoshells

Nanoshells self-assembled from biomacromolecules are common in biology but not among inorganic nanomaterials due to difficulties with replication of spherical tiling without molecular precision of folded biomolecules. Here, we show that semiconductor nanoparticles can spontaneously organize into porous nanoshells without specific lock-and-key interactions. The association of stabilizer-free CdS nanoparticles into self-limited spherical capsules is the result of scale-modified electrostatic and dispersion forces. They cannot be described by DLVO theory whereas molecular dynamics simulations with atomistic description of nanoparticles and solvent reveal the conditions necessary for the emergence of nanoshells. Morphology of the simulated assemblies formed under different conditions matched nearly perfectly the TEM tomography data. This study bridges the gap between biological and inorganic self-assembling nanosystems and conceptualizes a new pathway to spontaneous compartmentalization for a wide range of natural and man-made inorganic nanoparticles.