Peptidic Ligands to Control the Three‐Dimensional Self‐Assembly of Quantum Rods in Aqueous Media

Abstract

The use of peptidic ligands is validated as a generic chemical platform allowing one to finely control the organization in solid phase of semiconductor nanorods originally dispersed in an aqueous media. An original method to generate, on a macroscopic scale and with the desired geometry, three-dimensional supracrystals composed of quantum rods is introduced. In a first step, nanorods are transferred in an aqueous phase thanks to the substitution of the original capping layer by peptidic ligands. Infrared and nuclear magnetic resonance spectroscopy data prove that the exchange is complete; fluorescence spectroscopy demonstrates that the emitter optical properties are not significantly altered; electrophoresis and dynamic light scattering experiments assess the good colloidal stability of the resulting aqueous suspension. In a second step, water evaporation in a microstructured environment yields superstructures with a chosen geometry and in which nanorods obey a smectic B arrangement, as shown by electron microscopy. Incidentally, bulk drying in a capillary tube generates a similar local order, as evidenced by small angle X-ray scattering.

Self-Organization of Quantum Rods Induced by Lipid Membrane Corrugations

“…We previously reported the synthesis and surface functionalization of QRs. 19 Due to their shape and their net negative surface charge, QRs can be used instead of DNA, as was previously demonstrated, 14 which strengthens the system. Phospholipidic systems are known to undergo phase transitions depending on the temperature.…”

Controlling the Emission Properties of Quantum Rods via Multiscale 3D Ordered Organization

“…Starting from the same batch of quasispherical CdSe seeds, we synthesized hydrophobic QRs of different lengths using a slightly modified version [37,38] of the protocol reported by Carbone et al [39,40] (see Supporting Information for details). These QRs are obtained solubilized in toluene and are stabilized by a mixture of trioctyl phosphine oxide (TOPO), octadecylphosphonic acid (ODPA), and hexylphosphonic acid (HPA) (Figure 1(a)).…”

“…More specifically, as predicted by Onsager's theory [23,24], it has been demonstrated that anisotropic semiconductor nanocrystals, also named quantum rods (QR), exhibit a rich polymorphism, which includes nematic and smectic liquid crystal phases [10,[33][34][35]. Previously, we have described a simple, yet powerful, strategy for shaping self-assemblies of water-soluble rod-like nanoparticles, either gold nanorods [36] or QRs [37]: an aqueous suspension is imprinted between a flat substrate and a topologically micropatterned mold, and, after water has evaporated, walls displaying a smectic B packing are obtained, organized on a regular lattice over several square millimeters. On the basis of this work, we here more deeply report on the influence of a variation of the QR aspect ratio on the structural properties of the obtained supracrystals.…”

Hybrid gold nanoparticle–quantum dot self-assembled nanostructures driven by complementary artificial proteins

“…The dissolution of the QD-A3 was realized by incubation in acidic HCl solution during 12 hours according to the literature. 27 Standard A3 solutions at different concentrations from a stock solution (concentration 37 µM) were prepared in Na Phosphate buffer (pH 7.4) and the fluorescent intensity v.s. concentration was measured.…”