(420ag) Mechanism of Nanoparticle Assembly in Polymer Thin Films from Quantitative SEM Image Analysis

Nanoparticle self-assembly is being widely explored as a powerful, scalable, and inexpensive method for fabricating nanostructures. Recently, we demonstrated the self-assembly of shaped metal nanoparticles into chains of nanoparticles within a polymer thin-film for plasmonic applications [1]. The mechanism of assembly in such systems is still poorly understood, although such knowledge is essential for controlling the structures that are formed. We have developed an automated image analysis tool to extract detailed information about the assembly morphology from SEM images. This information in turn allows us to make quantitative comparisons with theory and simulations to predict the mechanism of assembly. I will present the results of our study, where we have found that the assembly process is well described by the diffusion-limited cluster-cluster aggregation mechanism. I will also describe our image analysis tool, scaling analyses, and general approach, which should prove helpful to other researchers in the field.

[1] B. Gao, G. Arya, and A. R. Tao, Nature Nanotechnology 2012, 7, 433-436.