Directed self-assembly of nanoscale building blocks through coded bonding potentials
Submitter: Jason J. Benkoski*
Mentor: Alamgir Karim
Category: Materials
Polymers Division, MSEL
Building 224, Room A225
Ph.: 301-975-8556 Fax: 301-975-3928
100 Bureau Dr., Stop 8541
Gaithersburg, MD 20899-8541
* not a Sigma Xi member
We present a novel platform for the formation of 2-D assemblies from nanoscale building blocks. The system consists of an oil-water interface in which the oil can be flash cured upon UV exposure. Mixed with a radical photoinitiator, 1,12-dodecanediol dimethacrylate solidifies in less than 5 seconds when exposed to UV light at an intensity of 8 mW/cm2. The rapid crosslinking allows one to obtain a “snapshot” of the self-assembly process for particles that segregate to the oil/water interface. Among the particles investigated were 400 nm PMMA latex spheres, 10 nm quantum dots, magnetite nanoparticles, and colloidosomes. The agglomerates formed by this process were typically either globular or fractal-like in appearance. By comparing with simulation, we find that the morphology of the aggregates is coded directly in the particles through the symmetry of the bonding potentials and the relative strengths of the interactions.