Self-Assembly of Shape-Tunable Oblate Colloidal Particles into Orientationally Ordered Crystals, Glassy Crystals and Plastic Crystals

Multilayer Self-Assemblies as Electronic and Optical Materials

MRS Proceedings ◽

10.1557/proc-488-401 ◽

1997 ◽

Vol 488 ◽

Cited By ~ 1

Author(s):

DeQuan Li ◽

M. Lütt ◽

Xiaobo Shi ◽

M. R. Fitzsimmons

Keyword(s):

Thin Film ◽

Self Assembly ◽

Film Growth ◽

Building Blocks ◽

Layer Growth ◽

The Self ◽

Growth Surface ◽

Layer By Layer ◽

Self Assembled ◽

Average Electron

AbstractThe layer-by-layer growth of film structures consisting of sequential depositions of oppositely charged polymers and macrocycles (ring-shaped molecules) have been constructed using molecular self-assembly techniques. These self-assembled thin films were characterized with X-ray reflectometry, which yielded (1) the average electron density, (2) the average thicknesses, and (3) the roughness of the growth surface of the self-assembled multilayer of macrocycles and polymers. These observations suggest that inorganic-organic interactions play an important role during the initial stages of thin-film growth, but less so as the thin film becomes thicker. Optical absorption techniques were also used to characterize the self-assembled multilayers. Phorphyrin and phthalocyanine derivatives were chosen as the building blocks of the self-assembled multilayers because of their interesting optical properties.

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Bifurcation of self-assembly pathways to sheet or cage controlled by kinetic template effect

Communications Chemistry ◽

10.1038/s42004-019-0232-2 ◽

2019 ◽

Vol 2 (1) ◽

Cited By ~ 5

Author(s):

Leonardo Hayato Foianesi-Takeshige ◽

Satoshi Takahashi ◽

Tomoki Tateishi ◽

Ryosuke Sekine ◽

Atsushi Okazawa ◽

...

Keyword(s):

Self Assembly ◽

Early Stage ◽

Building Blocks ◽

The Self ◽

Numerical Analyses ◽

Template Effect ◽

Self Assembled ◽

Assembly Pathways ◽

Formation Step

Abstract The template effect is a key feature to control the arrangement of building blocks in assemblies, but its kinetic nature remains elusive compared to the thermodynamic aspects, with the exception of very simple reactions. Here we report a kinetic template effect in a self-assembled cage composed of flexible ditopic ligands and Pd(II) ions. Without template anion, a micrometer-sized sheet is kinetically trapped (off-pathway), which is converted into the thermodynamically most stable cage by the template anion. When the template anion is present from the start, the cage is selectively produced by the preferential cyclization of a dinuclear intermediate (on-pathway). Quantitative and numerical analyses of the self-assembly of the cage on the on-pathway revealed that the accelerating effect of the template is stronger for the early stage reactions of the self-assembly than for the final cage formation step itself, indicating the kinetic template effect.

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Mikto-Arm Stars as Soft-Patchy Particles: From Building Blocks to Mesoscopic Structures

Polymers ◽

10.3390/polym13071114 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1114

Author(s):

Petra Bačová ◽

Dimitris G. Mintis ◽

Eirini Gkolfi ◽

Vagelis Harmandaris

Keyword(s):

Polymer Nanocomposites ◽

Self Assembly ◽

Nearest Neighbor ◽

Building Blocks ◽

Model System ◽

The Self ◽

Mutual Orientation ◽

Patchy Particles ◽

Self Assembled ◽

The Individual

We present an atomistic molecular dynamics study of self-assembled mikto-arm stars, which resemble patchy-like particles. By increasing the number of stars in the system, we propose a systematic way of examining the mutual orientation of these fully penetrable patchy-like objects. The individual stars maintain their patchy-like morphology when creating a mesoscopic (macromolecular) self-assembled object of more than three stars. The self-assembly of mikto-arm stars does not lead to a deformation of the stars, and their shape remains spherical. We identified characteristic sub-units in the self-assembled structure, differing by the mutual orientation of the nearest neighbor stars. The current work aims to elucidate the possible arrangements of the realistic, fully penetrable patchy particles in polymer matrix and to serve as a model system for further studies of nanostructured materials or all-polymer nanocomposites using the mikto-arm stars as building blocks.

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Role of Entropy in Colloidal Self-Assembly

Entropy ◽

10.3390/e22080877 ◽

2020 ◽

Vol 22 (8) ◽

pp. 877

Author(s):

Brunno C. Rocha ◽

Sanjib Paul ◽

Harish Vashisth

Keyword(s):

Free Energy ◽

Self Assembly ◽

Biomedical Applications ◽

Colloidal Particles ◽

The Self ◽

Crystalline Structures ◽

Hard Particles ◽

Recent Advances ◽

Self Assembled

Entropy plays a key role in the self-assembly of colloidal particles. Specifically, in the case of hard particles, which do not interact or overlap with each other during the process of self-assembly, the free energy is minimized due to an increase in the entropy of the system. Understanding the contribution of entropy and engineering it is increasingly becoming central to modern colloidal self-assembly research, because the entropy serves as a guide to design a wide variety of self-assembled structures for many technological and biomedical applications. In this work, we highlight the importance of entropy in different theoretical and experimental self-assembly studies. We discuss the role of shape entropy and depletion interactions in colloidal self-assembly. We also highlight the effect of entropy in the formation of open and closed crystalline structures, as well as describe recent advances in engineering entropy to achieve targeted self-assembled structures.

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Evolution of Carbon Self-Assembly in Colloidal Phase Diagram

MRS Proceedings ◽

10.1557/proc-739-h6.10 ◽

2002 ◽

Vol 739 ◽

Cited By ~ 1

Author(s):

V. Bouda

Keyword(s):

Phase Diagram ◽

Phase Transitions ◽

Self Assembly ◽

Colloidal Particles ◽

Thermal Fluctuation ◽

Ionic Concentration ◽

The Self ◽

Colloidal Systems ◽

Carbon Particles ◽

Self Assembled

ABSTRACTThe growth of the self-assembled structure of carbon colloidal particles has been studied [1]. The system of carbon particles was processed in electrical field in polymer melt with controlled ionic concentration. The interpretation of the complex evolution of the self-assembled structure of carbon particles was given in terms of phase transitions of colloidal systems of carbon particles.Interactions between doublets of carbon black (CB) particles are interpreted in terms of DLVO approximation of interaction energy as multiples of average thermal fluctuation kT. Plots of the sum of energy of electrostatic repulsion and energy of van der Waals attraction versus separation between the doublets show the energy barriers to coagulation of high B and the energy wells with the secondary minima of depth W. The colloidal phase transitions appear at critical conjuncture of the concentration of ions in the medium and surface potential on the colloids. Six transition lines determine five phases of the assembly of carbon colloids in the proposed colloidal phase diagram: lateral vapor + axial vapor (vapor), lateral liquid + axial vapor (columnar liquid crystal), lateral liquid + axial liquid (smectic LC), lateral liquid + axial solid (nematic LC), and lateral solid + axial solid (solid).The diagram provides a tool to control the evolution of carbon self-assembly. The eventual morphology depends on the route of the steps of the processing. During the time elapsed in the LC state, the structure can reorganize and the eventual coagulation produces various crystals. On the contrary, the route outside the LC state can produce glass.

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Self-assembly of amino acids toward functional biomaterials

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.12.85 ◽

2021 ◽

Vol 12 ◽

pp. 1140-1150

Author(s):

Huan Ren ◽

Lifang Wu ◽

Lina Tan ◽

Yanni Bao ◽

Yuchen Ma ◽

...

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Self Assembly ◽

Functional Materials ◽

Building Blocks ◽

The Self ◽

Self Assembled ◽

Functional Biomaterials ◽

Proteins And Peptides

Biomolecules, such as proteins and peptides, can be self-assembled. They are widely distributed, easy to obtain, and biocompatible. However, the self-assembly of proteins and peptides has disadvantages, such as difficulty in obtaining high quantities of materials, high cost, polydispersity, and purification limitations. The difficulties in using proteins and peptides as functional materials make it more complicate to arrange assembled nanostructures at both microscopic and macroscopic scales. Amino acids, as the smallest constituent of proteins and the smallest constituent in the bottom-up approach, are the smallest building blocks that can be self-assembled. The self-assembly of single amino acids has the advantages of low synthesis cost, simple modeling, excellent biocompatibility and biodegradability in vivo. In addition, amino acids can be assembled with other components to meet multiple scientific needs. However, using these simple building blocks to design attractive materials remains a challenge due to the simplicity of the amino acids. Most of the review articles about self-assembly focus on large molecules, such as peptides and proteins. The preparation of complicated materials by self-assembly of amino acids has not yet been evaluated. Therefore, it is of great significance to systematically summarize the literature of amino acid self-assembly. This article reviews the recent advances in amino acid self-assembly regarding amino acid self-assembly, functional amino acid self-assembly, amino acid coordination self-assembly, and amino acid regulatory functional molecule self-assembly.

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Homochiral Supramolecular Thin Film from Self-Assembly of Achiral Triarylamine Molecules by Circularly Polarized Light

Molecules ◽

10.3390/molecules25020402 ◽

2020 ◽

Vol 25 (2) ◽

pp. 402

Author(s):

Changjun Park ◽

Jinhee Lee ◽

Taehyoung Kim ◽

Jaechang Lim ◽

Jeyoung Park ◽

...

Keyword(s):

Thin Film ◽

Thin Films ◽

Self Assembly ◽

Polarized Light ◽

Building Blocks ◽

The Self ◽

Assembly Process ◽

Circularly Polarized Light ◽

Circularly Polarized ◽

Self Assembled

Here, we report the formation of homochiral supramolecular thin film from achiral molecules, by using circularly polarized light (CPL) only as a chiral source, on the condition that irradiation of CPL does not induce a photochemical change of the achiral molecules. Thin films of self-assembled structures consisting of chiral supramolecular fibrils was obtained from the triarylamine derivatives through evaporation of the self-assembled triarylamine solution. The homochiral supramolecular helices with the desired handedness was achieved by irradiation of circularly polarized visible light during the self-assembly process, and the chiral stability of supramolecular self-assembled product was achieved by photopolymerization of the diacetylene moieties at side chains of the building blocks, with irradiation of circularly polarized ultraviolet light. This work provides a novel methodology for the generation of homochiral supramolecular thin film from the corresponding achiral molecules.

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Pt and Pt–Rh supercrystals self-assembled in N,N-dimethylformamide

Chemical Communications ◽

10.1039/c6cc01110a ◽

2016 ◽

Vol 52 (28) ◽

pp. 5023-5026 ◽

Cited By ~ 4

Author(s):

Lin-Xiu Dai ◽

Xin-Yu Wang ◽

Xiao-Yu Zheng ◽

Ya-Wen Zhang

Keyword(s):

Self Assembly ◽

Building Blocks ◽

The Self ◽

Structure Directing Agent ◽

Self Assembled ◽

Specific Agent

N,N-Dimethylformamide (DMF) serves as the facet-specific agent for the formation of a cubic shape and the structure-directing agent for the self-assembly of Pt and Pt–Rh building blocks of the supercrystals.

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Nanoscale Self-Assembly Using Ion and Electron Beam Techniques: A Rapid Review

MRS Advances ◽

10.1557/adv.2020.349 ◽

2020 ◽

Vol 5 (64) ◽

pp. 3507-3520

Author(s):

Chunhui Dai ◽

Kriti Agarwal ◽

Jeong-Hyun Cho

Keyword(s):

Electron Beam ◽

Self Assembly ◽

Ion Beam ◽

Three Dimensional ◽

The Self ◽

Stress Generation ◽

Rapid Review ◽

High Yield ◽

3D Nanostructures ◽

Self Assembled

AbstractNanoscale self-assembly, as a technique to transform two-dimensional (2D) planar patterns into three-dimensional (3D) nanoscale architectures, has achieved tremendous success in the past decade. However, an assembly process at nanoscale is easily affected by small unavoidable variations in sample conditions and reaction environment, resulting in a low yield. Recently, in-situ monitored self-assembly based on ion and electron irradiation has stood out as a promising candidate to overcome this limitation. The usage of ion and electron beam allows stress generation and real-time observation simultaneously, which significantly enhances the controllability of self-assembly. This enables the realization of various complex 3D nanostructures with a high yield. The additional dimension of the self-assembled 3D nanostructures opens the possibility to explore novel properties that cannot be demonstrated in 2D planar patterns. Here, we present a rapid review on the recent achievements and challenges in nanoscale self-assembly using electron and ion beam techniques, followed by a discussion of the novel optical properties achieved in the self-assembled 3D nanostructures.

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