(516e) Dynamics and Drying-Induced Assembly of Shape-Anisotropic Nanoparticles

Supraparticles assembled from nanoparticles are promising materials for catalysis, gas adsorption, drug encapsulation, and photonics. A supraparticle’s properties and function are strongly connected to its internal structure. This structure is known to depend on the nanoparticles and how the supraparticle was fabricated, e.g., by casting a droplet and removing the solvent at a certain rate. There is particular interest to use nanoparticles with anisotropic shapes (such as rods) to create supraparticles with controlled porosity or optical properties, but there are significant gaps in our understanding of, and hence ability to engineer, this dynamic self-assembly process. Here, we first use mesoscale particle-based simulations (multiparticle collision dynamics method) to study the dynamics of various shape-anisotropic nanoparticles (octahedra, cubes, tetrahedra, and spherocylinders) in bulk suspensions. We then use simulations in close collaboration with experiments to investigate the properties of supraparticles self-assembled from either rod-like nanoparticles or a mixture of rod-like and spherical nanoparticles. Our work sheds important insight into the dynamics of shape-anisotropic nanoparticles and suggests strategies for tuning the structure, and hence properties, of supraparticles made from them.