Publications by authors named "Wajdi Chaabani"

Article Synopsis
  • Scientists try to copy nature's amazing structures, but making complex supercrystals from tiny particles (called nanoparticles) is hard because they're usually very symmetrical.
  • This study looks at how the shape of these nanoparticles and their shapes' confinement in specially designed molds can help them stick together to form new supercrystals.
  • The researchers found that the edges of the mold help direct the growth of the crystals and that having flat surfaces is important for making sure they grow the right way, which could help create new types of materials.
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Depletion-induced self-assembly is routinely used to separate plasmonic nanoparticles (NPs) of different shapes, but less often for its ability to create supercrystals (SCs) in suspension. Therefore, these plasmonic assemblies have not yet reached a high level of maturity and their in-depth characterization by a combination of in situ techniques is still very much needed. In this work, gold triangles (AuNTs) and silver nanorods (AgNRs) are assembled by depletion-induced self-assembly.

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Packing solid shapes into regular lattices can yield very complex assemblies, not all of which achieve the highest packing fraction. In two dimensions, the regular pentagon is paradigmatic, being the simplest shape that does not pave the plane completely. In this work, we demonstrate the packing of plasmonic nanoprisms with pentagonal cross section, which form extended supercrystals.

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In this work, various LiZnPO:0.5 mol% Ln (Ln = Ho, Er) phosphors with different Yb ion doping concentrations were synthesized by a sol-gel/Pechini method. X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques were used to evaluate the phase and morphology of the samples.

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Pentagonal packing is a long-standing issue and a rich mathematical topic, brought to the fore by recent progress in nanoparticle design. Gold pentagonal bipyramids combine fivefold symmetry and anisotropy and their section varies along the length. In this work, colloidal supercrystals of pentagonal gold bipyramids are obtained in a compact arrangement that generalizes the optimal packing of regular pentagons in the plane.

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High index dielectric nanoparticles have been proposed for many different applications. However, widespread utilization in practice also requires large-scale production methods for crystalline silicon nanoparticles, with engineered optical properties in a low-cost manner. Here, we demonstrate a facile, low-cost, and large-scale fabrication method of crystalline silicon colloidal Mie resonators in water, using a blender.

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