  This article explores the governing role of the internal hydrodynamics and
advective transport within sessile colloidal droplets on the self assembly of
nanostructures to form floral patterns. Water acetone binary fluid and Bi2O3
nanoflakes based complex fluids are experimented with. Microliter sessile
droplets are allowed to vaporize and the dry out patterns are examined using
scanning electron microscopy. The presence of distributed self assembled rose
like structures is observed. The population density, structure and shape of the
floral structures are noted to be dependent on the binary fluid composition and
nanomaterial concentration. Detailed microscopic particle image velocimetry
analysis is undertaken to qualitatively and quantitatively describe the solutal
Marangoni advection within the evaporating droplets. It has been shown that the
kinetics, regime and location of the internal advection are responsible factors
towards the hydrodynamics influenced clustering, aggregation and self-assembly
of the nanoflakes. In addition, the size of the nanostructures and the complex
fluids.
