Dmitry Baranov
Associate senior lecturer
Multilayer Diffraction Reveals That Colloidal Superlattices Approach the Structural Perfection of Single Crystals
Author
Summary, in English
Colloidal superlattices are fascinating materials made of ordered
nanocrystals, yet they are rarely called “atomically precise”. That is
unsurprising, given how challenging it is to quantify the degree of
structural order in these materials. However, once that order crosses a
certain threshold, the constructive interference of X-rays diffracted by
the nanocrystals dominates the diffraction pattern, offering a wealth
of structural information. By treating nanocrystals as scattering
sources forming a self-probing interferometer, we developed a multilayer
diffraction method that enabled the accurate determination of the
nanocrystal size, interparticle spacing, and their fluctuations for
samples of self-assembled CsPbBr3 and PbS nanomaterials. The
multilayer diffraction method requires only a laboratory-grade
diffractometer and an open-source fitting algorithm for data analysis.
The average nanocrystal displacement of 0.33 to 1.43 Å in the studied
superlattices provides a figure of merit for their structural perfection
and approaches the atomic displacement parameters found in traditional
crystals.
nanocrystals, yet they are rarely called “atomically precise”. That is
unsurprising, given how challenging it is to quantify the degree of
structural order in these materials. However, once that order crosses a
certain threshold, the constructive interference of X-rays diffracted by
the nanocrystals dominates the diffraction pattern, offering a wealth
of structural information. By treating nanocrystals as scattering
sources forming a self-probing interferometer, we developed a multilayer
diffraction method that enabled the accurate determination of the
nanocrystal size, interparticle spacing, and their fluctuations for
samples of self-assembled CsPbBr3 and PbS nanomaterials. The
multilayer diffraction method requires only a laboratory-grade
diffractometer and an open-source fitting algorithm for data analysis.
The average nanocrystal displacement of 0.33 to 1.43 Å in the studied
superlattices provides a figure of merit for their structural perfection
and approaches the atomic displacement parameters found in traditional
crystals.
Publishing year
2021-04-27
Language
English
Pages
6243-6256
Publication/Series
ACS Nano
Volume
15
Issue
4
Document type
Journal article
Publisher
The American Chemical Society (ACS)
Keywords
- disorder
- grazing-incidence
- multilayer diffraction
- nanocrystal
- superlattice
- thermal annealing
Status
Published
ISBN/ISSN/Other
- ISSN: 1936-0851