Colloidal chemistry with patchy silica nanoparticles

Abstract

We report a new route to synthesize clusters, or so-called colloidal molecules (CMs), which mimic the symmetry of molecular structures made of one central atom. We couple site-specifically functionalized patchy nanoparticles, i.e., valence-endowed colloidal atoms (CAs), with complementary nanospheres through amide bonds. By analogy with the Gillespie formalism, we show that AX4, AX3E1 and AX2E2 CMs can be obtained from tetravalent sp3-like CAs when the relative amount of both building units is varied in a controlled manner. We obtain AX2 CMs from divalent sp-like CAs. We also show that it is possible to covalently attach two different types of satellites to the same central patchy nanoparticle to create more complex CMs, opening the way to the fabrication of new multifunctional nanostructures with well-controlled shape and composition.

Dimpled SiO2@γ-Fe2O3 nanocomposites – fabrication and use for arsenic adsorption in aqueous medium

“…In our previous works, when we managed to combine gold NPs and silica structures in a range of congurations (not necessarily with gold being always located at the outer layer of silica), in most cases, pre-synthesized gold NPs were used. 7,8,[24][25][26][27] However, we also managed to obtain a regrowth stage for gold by using Au NP seeds, in somewhat different approaches. 6,28 Nanocomposites containing plasmonic satellite elements, such as gold, can nd applications as photonic materials, superlenses and sensors or in life sciences, optics and coating industry.…”

Patchy Nanoparticle Synthesis and Self-Assembly

“…In terms of self-assembly of patchy nanoparticles, different driving forces, including vdW, electrostatic, chemical and entropic interactions, have been explored. However, at current stage, most of the self-assembled structures are still limited to 0D cluster [30,104] and 1D chain structures [15,100,101,103]. Largescale 2D planar structure [18] or 3D lattices [148] have only been realized in a few examples with limited domain size, causing a delay in realizing potential applications in medicine, electronic devices, and photonic crystals.…”

“…Then the tip-modified AuNRs gradually assemble into linear chainlike structures when streptavidins are added to covalently "link" two disulfide groups (Figure 6a and b). Another recent example utilizes the chemical reaction between amine group and carboxyl group, inducing the self-assembly between concavely patched silica nanoparticles and spherical silica nanoparticles [104]. The self-assembled structures are clusters with sp, sp 2 , and sp 3 hybridized molecular structures (Figure 6c-h), which can be potentially used as building blocks for hierarchical self-assembly.…”

Synthesis of Colloidal Molecules: Recent Advances and Perspectives

“…cavities) that display well-defined symmetries can assemble with multiple complementary spherical particlesv ia depletion interaction [65] or spherical droplets via preferential wetting, [66] forming CMs with well-definedg eometries.W ed eveloped as imilars trategy in promoting the covalenta ttachment of complementary nanospheresw ith silica nanoparticles with 2, 3o r4dimples through the selective functionalization of PS residues remaining at the bottom of the dimples. [67,68] By varying the relative amountso fb oth precursors, the size or the chemicalc omposition of the complementary nanospheres, we createdal arge variety of CMs, including chiral ones (Figure 3c). An alternative approachisb ased on the use of particles with enthalpic patches, that is, zonesa tt heir surface which exhibit specific interactions, as precursors.…”