Flow Dichroism as a Reliable Method to Measure the Hydrodynamic Aspect Ratio of Gold Nanoparticles

• DOI: 10.1021/nn201033x
• Publication Date: 2011-05-05T12:50:05Z
• Authors: Naveen Krishna Reddy; Jorge Pérez-Juste; Isabel Pastoriza-...; Peter R. Lang; Jan K. G. Dhont; Luis M. Liz-Marzán; Jan Vermant
• Keywords: Dispersity; Aspect ratio (aeronautics); Particle (ecology)

Particle shape plays an important role in controlling the optical, magnetic, and mechanical properties of nanoparticle suspensions as well nanocomposites. However, characterizing size, shape, associated polydispersity nanoparticles is not straightforward. Electron microscopy provides accurate measurement geometric properties, but sample preparation can be laborious, to obtain statistically relevant data many particles need analyzed separately. Moreover, when are suspended a fluid, it measure their hydrodynamic they determine aspects such diffusion rheological behavior suspensions. Methods that evaluate dynamics light scattering rheo-optical methods accurately provide these do necessitate sufficient optical response. In present work, three different for nonspherical gold critically compared, especially taking into account complex response particles. The evaluated terms versatility asses polydispersity. Among these, technique shown most reliable method aspect ratio two reasons. First, use evolution orientation angle makes effects less important. Second, external flow field gives mathematically more robust relation between particle motion ratio, with relatively small ratios.