Anisotropic Self-Assembly of Organic–Inorganic Hybrid Microtoroids

Abstract

Toroidal structures based on self-assembly of predesigned building blocks are well-established in the literature, but spontaneous self-organization to prepare such structures has not been reported to date. Here, organic-inorganic hybrid microtoroids synthesized by simultaneous coordination-driven assembly of amphiphilic molecules and hydrophilic polymers are reported. Mixing amphiphilic molecules with iron(III) chloride and hydrophilic polymers in water leads, within minutes, to the formation of starlike nanostructures. A spontaneous self-organization of these nanostructures is then triggered to form stable hybrid microtoroids. Interestingly, the toroids exhibit anisotropic hierarchical growth, giving rise to a layered toroidal framework. These microstructures are mechanically robust and can act as templates to host metallic nanoparticles such as gold and silver. Understanding the nature of spontaneous assembly driven by coordination multiple non-covalent interactions can help explain the well-ordered complexity of many biological organisms in addition to expanding the available tools to mimic such structures at a molecular level.

Polymeric Toroidal Self‐Assemblies: Diverse Formation Mechanisms and Functions

“…In the field of photoelectronics, toroidal structures assembled from building blocks of light-responsive groups or organicinorganic hybrids can exhibit unique optical properties. [173,174] For example, Maji et al found that the vesicles and toroids of metal-organic molecules show efficient funneling of excitation energy and hence may be used as a light-harvesting antenna. [173] In brief, the applications of toroids in these fields are emerging.…”

Systematic study on evolution of self-assembly morphologies of CABC tetrablock terpolymers with varied segment lengths

“…14 Because of the hollow structure, toroids are also used as scaffolds for fabricating organic and inorganic nanostructures with pores. 15,16 Polymer toroids have successfully been obtained using diblock and tri-block copolymers via sophisticated design in several factors such as the kind, length, and composition of each block segment, the preparation procedure, and the solvent property. [17][18][19] For example, a poly(acrylic acid)-bpoly(methyl acrylate)-b-polystyrene ABC-type tri-block copolymer 11 and a polystyrene-b-poly(4-vinypyridine)-bpolystyrene ABA-type tri-block copolymer 20 generated toroids.…”

A comparative study of the self-assembly of achiral and chiral hairy nanoparticles with polystyrene cores and poly(2-hydroxyethylmethacrylate) hairs

“…16 At the nanoscale, the ability of polymeric nanoparticles to assemble to generate functional materials can lead to improved functional properties. 17 The unique self-assembling property of block copolymers which can adopt a broad variety of morphologies, such as, lamellar, toroidal, cylindrical and spherical structures depending on the type and relative volume fractions of the blocks. [18][19][20][21] Nanoparticles self-assembly process can be triggered by environmental factors including temperature, pH or solvent polarity in a broad range of applications.…”