Spreading Ag Nanocrystals from Liquid to Solid Surface via Marangoni Flow
Spontaneous fluid flow is observed when a volume of passivated Ag nanocrystals dispersed in chloroform is mixed with a water/ethanol (v/v) mixture containing acidified 11-mercaptoundecanoic acid. Once mixed, a reddish film, uniformly embedded with Ag nanocrystals as measured by transmission electron microscopy, climbs the interior surface of the glass vessel. This phenomenon is recorded by video, and a measurement of the height of the film front traveled in time is analyzed. Assumptions and boundary conditions applied to the Navier-Stokes equation for continuum fluid flow in one-dimension yield a velocity expression for the film flow. The velocity expression contains terms that account for Marangoni flow (flow induced by surface tension gradients), capillary flow, and gravity effects. Preliminary analysis suggests film flow is due to the Marangoni effect.
Johnson, Donald, " Spreading Ag Nanocrystals from Liquid to Solid Surface via Marangoni Flow" (2007). URC Student Scholarship.
Camille and Henry Dreyfus Foundation Grant