Revealing the impact of polystyrene-functionalization of Au octahedral nanocrystals of different sizes on formation and structure of mesocrystals

Dmitry Lapkin; Shweta Singh; Felizitas Kirner; Sebastian Sturm; Dameli Assalauova; Alexandr Ignatenko; Thomas Wiek; Thomas Gemming; Axel Lubk; Knut Müller-Caspary; Azat Khadiev; Dmitri Novikov; Elena V. Sturm; Ivan A. Vartanyants

arXiv · 2306.14507

Revealing the impact of polystyrene-functionalization of Au octahedral nanocrystals of different sizes on formation and structure of mesocrystals

Dmitry Lapkin·Shweta Singh·Felizitas Kirner·Sebastian Sturm·Dameli Assalauova·Alexandr Ignatenko·Thomas Wiek·Thomas Gemming·Axel Lubk·Knut Müller-Caspary·Azat Khadiev·Dmitri Novikov·Elena V. Sturm·Ivan A. Vartanyants

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Abstract

The self-assembly of anisotropic nanocrystals (stabilized by organic capping molecules) with pre-selected composition, size, and shape allows for the creation of nanostructured materials with unique structures and features. For such a material, the shape and packing of the individual nanoparticles play an important role. This work presents a synthesis procedure for ω-thiol-terminated polystyrene (PS-SH) functionalized gold nanooctahedra of variable size (edge length 37, 46, 58, and 72 nm). The impact of polymer chain length (Mw: 11k, 22k, 43k, and 66k g/mol) on the growth of colloidal crystals (e.g. mesocrystals) and their resulting crystal structure is investigated. Small-angle X-ray scattering (SAXS) and scanning transmission electron microscopy (STEM) methods provide a detailed structural examination of the self-assembled faceted mesocrystals based on octahedral gold nanoparticles of different size and surface functionalization. Three-dimensional angular X-ray cross-correlation analysis (AXCCA) enables high-precision determination of the superlattice structure and relative orientation of nanoparticles in mesocrystals. This approach allows us to perform non-destructive characterization of mesocrystalline materials and reveals their structure with resolution down to the nanometer scale.

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Dmitry Lapkin, Shweta Singh, Felizitas Kirner, Sebastian Sturm, Dameli Assalauova, Alexandr Ignatenko, Thomas Wiek, Thomas Gemming, Axel Lubk, Knut Müller-Caspary, Azat Khadiev, Dmitri Novikov, Elena V. Sturm, Ivan A. Vartanyants. 2023-06-26. Revealing the impact of polystyrene-functionalization of Au octahedral nanocrystals of different sizes on formation and structure of mesocrystals. https://arxiv.org/abs/2306.14507

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