Laboratory Studies Investigating the Influence of Particle Diameter on Viscosity

Visibility, cloud formation, climate and human health are affected by suspended particles that are smaller than 100 nm in size, yet, many key particle properties remain ill-defined. In this project, novel experimental techniques are used to increase understanding of how particle viscosity changes with size. Results will help explain and predict atmospheric chemical processes with implications on climate and human health, as well as apply to a wide range of fields where nanoparticles are present.

Graduate and undergraduate students will be an integral part of the work, and outreach activities are planned for high school students.

As particle size decreases, strong curvature of the particle-air interface leads to deviations in physical properties from those observed in bulk materials. Viscosity is one such property, which dependence on particle size is poorly understood, yet, viscosity plays key roles in diffusion and reaction rates affecting atmospheric chemistry, global climate and human health.

To shed light on the particle size-viscosity relationship, the present study seeks to quantify how solid-liquid phase transitions are influenced by particle diameter between 10 and 100 nm. Particular focus is on