Tunable dipolar capillary deformations for magnetic Janus particles at fluid–fluid interfaces

We present theory and simulations describing the behaviour of magnetic Janus particles adsorbed at fluid–fluid interfaces interacting with an external magnetic field. We show that the particles deform the interface in a dipolar manner and suggest how to utilise capillary interactions to create novel, reconfigurable materials.

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Sensitivity of PS/CoPd Janus particles to an external magnetic field

RSC Advances ◽

10.1039/d1ra02410h ◽

2021 ◽

Vol 11 (28) ◽

pp. 17051-17057

Author(s):

Anna Eichler-Volf ◽

Yara Alsaadawi ◽

Fernando Vazquez Luna ◽

Qaiser Ali Khan ◽

Simon Stierle ◽

...

Keyword(s):

Magnetic Field ◽

Magnetic Properties ◽

External Magnetic Field ◽

Magnetic Fields ◽

Janus Particles ◽

Weak Magnetic Fields

PS/CoPd Janus particles respond very sensitively to application of low external magnetic fields. Owing to the magnetic properties, the PS/CoPd particles may be used, for example, to sense the presence of weak magnetic fields as micro-magnetometers.

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Capillary interactions between spherical Janus particles at liquid–fluid interfaces

Soft Matter ◽

10.1039/c3sm27380f ◽

2013 ◽

Vol 9 (13) ◽

pp. 3640 ◽

Cited By ~ 40

Author(s):

Hossein Rezvantalab ◽

Shahab Shojaei-Zadeh

Keyword(s):

Janus Particles ◽

Fluid Interfaces ◽

Capillary Interactions

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Equilibrium configurations and capillary interactions of Janus dumbbells and spherocylinders at fluid–fluid interfaces

Soft Matter ◽

10.1039/c8sm02361a ◽

2019 ◽

Vol 15 (12) ◽

pp. 2638-2647 ◽

Cited By ~ 8

Author(s):

Carmine Anzivino ◽

Fuqiang Chang ◽

Giuseppe Soligno ◽

René van Roij ◽

Willem K. Kegel ◽

...

Keyword(s):

Numerical Method ◽

Experimental Results ◽

Janus Particles ◽

Fluid Interfaces ◽

Fluid Interface ◽

Equilibrium Configurations ◽

Capillary Interactions ◽

Good Agreement

We numerically investigate the adsorption of a variety of Janus particles (dumbbells, elongated dumbbells and spherocylinders) at a fluid–fluid interface by using a numerical method that takes into account the interfacial deformations. We also experimentally synthesize micrometer–sized charged Janus dumbbells and let them adsorb at a water–decane interface. We find a good agreement between numerical and experimental results.

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The magnetization of dense aggregated dipolar fluids

Analecta Technica Szegedinensia ◽

10.14232/analecta.2018.2.1-12 ◽

2018 ◽

Vol 12 (2) ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Sándor Nagy

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

External Field ◽

Hard Sphere ◽

Canonical Ensemble ◽

Present Theory ◽

Hard Sphere Fluid ◽

Ensemble Monte Carlo ◽

Dipolar Fluids ◽

Theoretical Results

The magnetization for dipolar fluids is studied treated separately at low and high external magnetic field. Canonical ensemble Monte Carlo simulations have been performed in dipolar hard sphere fluid in order to test these theoretical results. New expressions are introduced at low and high external field and ultimately the synthesized formula is given. The main difference in the structure of dipolar liquids at different external field is the average orientation of the formed chains. In case of infinitesimal external magnetic field there is no a well-specified direction, while at high enough external field actually the chains are parallel to this field. The present theory yields good result in the intermediate region as well where the most conspicuous failures are provided by the former theories.

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Fabrication of Novel Magnetic Janus Microparticles

MRS Proceedings ◽

10.1557/proc-1135-cc02-08 ◽

2008 ◽

Vol 1135 ◽

Author(s):

Amro K. F. Dyab ◽

Vesselin N. Paunov

Keyword(s):

Magnetic Field ◽

External Magnetic Field ◽

Magnetite Nanoparticles ◽

Janus Particles ◽

Ferromagnetic Behavior ◽

Water Emulsion ◽

Novel Technique ◽

Oil In Water ◽

Magnetic Filed ◽

Oil In Water Emulsion

ABSTRACTWe have designed a novel technique for fabrication of magnetic Janus microparticles based on “trapping” the alignment of magnetite nanoparticles dispersed within the oil drops of polymerizable oil-in-water emulsion. We polymerized the oil drops after gelling the continuous aqueous phase in the presence of an external magnetic filed. This allowed us to produce magnetic Janus particles with optical and magnetic anisotropy which form unusual zigzag chains and structures when an external magnetic field is applied to a suspension of such particles. These novel microparticles retain high remanence magnetization and coercivity values indicative of ferromagnetic behavior, which indicates that the composite polymeric Janus microparticles posses a net magnetic dipole and behave like micro-magnets due to the “trapped” orientation of the magnetite nanoparticles in their polymeric matrix.

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