Jump to main content
Jump to site search

Issue 12, 2014
Previous Article Next Article

Sharpening the surface of magnetic paranematic droplets

Author affiliations


In a non-uniform magnetic field, the droplets of colloids of nickel nanorods and nanobeads aggregate to form a cusp at the droplet surface not deforming the entire droplet shape. When the field is removed, nanorods diffuse away and the cusp disappears. Spherical particles can form cusps in a similar way, but they stay aggregated after the release of the field; finally, the aggregates settle down to the bottom of the drop. The X-ray phase contrast imaging reveals that nanorods in the cusps stay parallel to each other without visible spatial order of their centers of mass. The formation of cusps can be explained with a model that includes magnetostatic and surface tension forces. The discovered possibility of controlled assembly and quenching of nanorod orientation under the cusped liquid surface offers vast opportunities for alignment of carbon nanotubes, nanowires and nanoscrolls, prior to spinning them into superstrong and multifunctional fibers. Magnetostatic and electrostatic analogies suggest that a similar ideal alignment can be achieved with the rod-like dipoles subject to a strong electric field.

Graphical abstract: Sharpening the surface of magnetic paranematic droplets

Back to tab navigation

Supplementary files

Publication details

The article was received on 15 Oct 2013, accepted on 27 Nov 2013 and first published on 28 Nov 2013

Article type: Paper
DOI: 10.1039/C3SM52655K
Soft Matter, 2014,10, 1917-1923

  •   Request permissions

    Sharpening the surface of magnetic paranematic droplets

    A. Tokarev, W. Lee, I. Sevonkaev, D. Goia and K. G. Kornev, Soft Matter, 2014, 10, 1917
    DOI: 10.1039/C3SM52655K

Search articles by author