Self-Limiting Assembly of CdS Nanoparticles into Complex Corrugated Microparticles*

Inorganic nanoscale materials have been shown to self-assemble into microscale particles with highly corrugated geometries. However, the mechanism governing their formation remains an open question. Here, we present a joint computational and experimental study of a model system of uniformly-sized CdS-based corrugated particles (HPs) that self-assemble from polydisperse nanoparticles (NPs). We show that the topologies of corrugated particles originate from the thermodynamic preference of polydisperse NPs to attach to a nanoscale cluster where electrostatic repulsion competes with van der Waals attraction. Theoretical models and simulations of the self-assembly accounting for the competition of attractive and repulsive interactions in electrolytes accurately describe experimentally observed particle morphology, growth stages, and the spectrum of products. Our theory provides unique mechanistic insights into HP formation, allowing for a priori design of structurally complex materials with applications in catalysis, sensing, environmental remediation, and optics.