Abstract
The characterization of periodic order in assemblies of colloidal particles can be complicated by the coincidence of Bragg diffraction peaks of the structure and minima in the form factor of the particles. Here, we demonstrate a general strategy to overcome this problem that is applicable to all low-dimensional structures. This approach is demonstrated in the application of small-angle X-ray scattering (SAXS) for the characterization of monolayers of colloidal silica superballs prepared using the unidirectional rubbing method. In this method, the ordering of the colloidal superballs is achieved by mechanically rubbing them onto a polydimethylsiloxane (PDMS)-coated surface. Using three differently shaped superballs, ranging from spherical to almost cubic, we show that certain Bragg peaks may not appear in the diffraction patterns due to the presence of minima in the form factor. We show that these missing Bragg peaks can be visualized by imaging the colloidal monolayers at various orientations. Moreover, we argue that the same strategy can be applied to other techniques, such as neutron scattering.
Original language | English |
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Article number | 5117 |
Pages (from-to) | 1-12 |
Journal | Applied Sciences (Switzerland) |
Volume | 11 |
Issue number | 11 |
DOIs | |
Publication status | Published - 31 May 2021 |
Bibliographical note
Funding Information:Funding: This research was funded by NWO grant number 712.015.003 (D.N.t.N), 016.Veni.192.119 (J.-M.M.) and 195.068.1113 (ESRF beamtime).
Funding Information:
Acknowledgments: Dominique Thies-Weesie is thanked for her help with the preparation of the spherical silica colloids. Nicholas Orr is thanked for his help at the beamline of the ESRF. Michela Brunelli and Daniel Hermida Merino are thanked for providing technical support at the beamline. Cedric Gommes is thanked for useful discussions. The Nederlandse Organisatie voor Wetenschap-pelijk Onderzoek (NWO) is thanked for providing the financial support.
Publisher Copyright:
© 2020 by the authors. Licensee MDPI, Basel, Switzerland.
Funding
Funding: This research was funded by NWO grant number 712.015.003 (D.N.t.N), 016.Veni.192.119 (J.-M.M.) and 195.068.1113 (ESRF beamtime). Acknowledgments: Dominique Thies-Weesie is thanked for her help with the preparation of the spherical silica colloids. Nicholas Orr is thanked for his help at the beamline of the ESRF. Michela Brunelli and Daniel Hermida Merino are thanked for providing technical support at the beamline. Cedric Gommes is thanked for useful discussions. The Nederlandse Organisatie voor Wetenschap-pelijk Onderzoek (NWO) is thanked for providing the financial support.
Keywords
- Colloidal monolayers
- Colloidal superballs
- Form factor
- SAXS
- Scattering