Path-Dependent Self-Assembly of Magnetic Anisotropic Colloidal Peanuts
(2020) In Journal of Physical Chemistry B 124(27). p.5754-5760- Abstract
Here we present the field induced self-assembly of anisotropic colloidal particles whose shape resembles peanuts. Being made up of hematite core and silica shell, these particles align in a direction perpendicular to the applied external magnetic field. Using small-angle X-ray scattering with microradian resolution (μrad-SAXS) in sedimented samples, we have found that one can tune the self-assembled structures by changing the time of application of the external field. If the field is applied after the sedimentation, the self-assembled structure is a nematic one, while dipolar chains are formed if the field is applied during the sedimentation process. Interestingly, within each chain particles form a smectic phase with defects. Further,... (More)
Here we present the field induced self-assembly of anisotropic colloidal particles whose shape resembles peanuts. Being made up of hematite core and silica shell, these particles align in a direction perpendicular to the applied external magnetic field. Using small-angle X-ray scattering with microradian resolution (μrad-SAXS) in sedimented samples, we have found that one can tune the self-assembled structures by changing the time of application of the external field. If the field is applied after the sedimentation, the self-assembled structure is a nematic one, while dipolar chains are formed if the field is applied during the sedimentation process. Interestingly, within each chain particles form a smectic phase with defects. Further, these aforementioned nematic and smectic phases are of oblate type in spite of the prolate shape of the individual particles. For dipolar chains, an unusual diffraction peak shape has been observed with highly anisotropic tails in the transverse direction (perpendicular to the external field). The peak shape can be rationalized by considering the fact that the dipolar chains can act as a building block aligned along the field direction to form a para-nematic phase.
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- author
- Kamal, Md Arif LU ; Petukhov, Andrei V. and Pal, Antara LU
- organization
- publishing date
- 2020-07-09
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Journal of Physical Chemistry B
- volume
- 124
- issue
- 27
- pages
- 7 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85088207984
- pmid:32515962
- ISSN
- 1520-6106
- DOI
- 10.1021/acs.jpcb.0c03771
- language
- English
- LU publication?
- yes
- id
- ec89a388-c55b-451e-a1d9-c062fd201a6b
- date added to LUP
- 2021-01-12 10:57:28
- date last changed
- 2024-09-05 12:46:55
@article{ec89a388-c55b-451e-a1d9-c062fd201a6b,
abstract = {{<p>Here we present the field induced self-assembly of anisotropic colloidal particles whose shape resembles peanuts. Being made up of hematite core and silica shell, these particles align in a direction perpendicular to the applied external magnetic field. Using small-angle X-ray scattering with microradian resolution (μrad-SAXS) in sedimented samples, we have found that one can tune the self-assembled structures by changing the time of application of the external field. If the field is applied after the sedimentation, the self-assembled structure is a nematic one, while dipolar chains are formed if the field is applied during the sedimentation process. Interestingly, within each chain particles form a smectic phase with defects. Further, these aforementioned nematic and smectic phases are of oblate type in spite of the prolate shape of the individual particles. For dipolar chains, an unusual diffraction peak shape has been observed with highly anisotropic tails in the transverse direction (perpendicular to the external field). The peak shape can be rationalized by considering the fact that the dipolar chains can act as a building block aligned along the field direction to form a para-nematic phase.</p>}},
author = {{Kamal, Md Arif and Petukhov, Andrei V. and Pal, Antara}},
issn = {{1520-6106}},
language = {{eng}},
month = {{07}},
number = {{27}},
pages = {{5754--5760}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Journal of Physical Chemistry B}},
title = {{Path-Dependent Self-Assembly of Magnetic Anisotropic Colloidal Peanuts}},
url = {{http://dx.doi.org/10.1021/acs.jpcb.0c03771}},
doi = {{10.1021/acs.jpcb.0c03771}},
volume = {{124}},
year = {{2020}},
}