Quantifying Order during Field-driven Alignment of Colloidal Semiconductor Nanorods

Aligning large populations of colloidal nanorods (NRs) into ordered assemblies provides a strategy for engineering macroscopic functional materials with strong optical anisotropy. The bulk optical properties of such systems depend not only on the individual NR building blocks, but also on their meso- and macroscale ordering, in addition to more complex inter-particle coupling effects. Here, we investigate the dynamic alignment of colloidal CdSe/CdS NRs in the presence of AC electric fields by measuring concurrent changes in optical transmission. Our work identifies two distinct scales of interaction that give rise to the field-driven optical response: (1) the spontaneous mesoscale self-assembly of colloidal NRs into structures with increased optical anisotropy, and (2) the macroscopic ordering of NR assemblies along the direction of the applied AC field. By modeling the alignment of NR ensembles using directional statistics, we experimentally quantify the maximum degree of order in terms of the average deviation angle relative to the field axis. Results show a consistent improvement in alignment as a function of NR concentration—with a minimum average deviation of 18.7°—indicating that mesoscale assembly helps facilitate field-driven alignment of colloidal NRs.

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The Assembly of Porphyrin Systems in Well-Defined Nanostructures: An Update

Molecules ◽

10.3390/molecules24234307 ◽

2019 ◽

Vol 24 (23) ◽

pp. 4307 ◽

Cited By ~ 12

Author(s):

Gabriele Magna ◽

Donato Monti ◽

Corrado Di Natale ◽

Roberto Paolesse ◽

Manuela Stefanelli

Keyword(s):

Self Assembly ◽

Energy Transport ◽

Functional Materials ◽

Building Blocks ◽

Spatial Arrangement ◽

Transport Processes ◽

Internal Electric Field ◽

Porphyrin Derivatives ◽

Molecular Building Blocks ◽

The Individual

The interest in assembling porphyrin derivatives is widespread and is accounted by the impressive impact of these suprastructures of controlled size and shapes in many applications from nanomedicine and sensors to photocatalysis and optoelectronics. The massive use of porphyrin dyes as molecular building blocks of functional materials at different length scales relies on the interdependent pair properties, consisting of their chemical stability/synthetic versatility and their quite unique physicochemical properties. Remarkably, the driven spatial arrangement of these platforms in well-defined suprastructures can synergically amplify the already excellent properties of the individual monomers, improving conjugation and enlarging the intensity of the absorption range of visible light, or forming an internal electric field exploitable in light-harvesting and charge-and energy-transport processes. The countless potentialities offered by these systems means that self-assembly concepts and tools are constantly explored, as confirmed by the significant number of published articles related to porphyrin assemblies in the 2015–2019 period, which is the focus of this review.

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A Dynamic Route to Structure and Function: Recent Advances in Imine-Based Organic Nanostructured Materials

Australian Journal of Chemistry ◽

10.1071/ch12349 ◽

2013 ◽

Vol 66 (1) ◽

pp. 9 ◽

Cited By ~ 26

Author(s):

Yi Liu ◽

Zhan-Ting Li

Keyword(s):

Self Assembly ◽

Reaction System ◽

Functional Materials ◽

Building Blocks ◽

The Self ◽

Interlocked Molecules ◽

Functional Aspects ◽

Imine Bond ◽

And Function ◽

Dynamic Route

The chemistry of imine bond formation from simple aldehyde and amine precursors is among the most powerful dynamic covalent chemistries employed for the construction of discrete molecular objects and extended molecular frameworks. The reversible nature of the C=N bond confers error-checking and proof-reading capabilities in the self-assembly process within a multi-component reaction system. This review highlights recent progress in the self-assembly of complex organic molecular architectures that are enabled by dynamic imine chemistry, including molecular containers with defined geometry and size, mechanically interlocked molecules, and extended frameworks and polymers, from building blocks with preprogrammed steric and electronic information. The functional aspects associated with the nanometer-scale features not only place these dynamically constructed nanostructures at the frontier of materials sciences, but also bring unprecedented opportunities for the discovery of new functional materials.

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Straightforward Preparation of Supramolecular Janus Nanorods by Hydrogen Bonding of End-Functionalized Polymers

10.26434/chemrxiv.12206384.v1 ◽

2020 ◽

Author(s):

Shuaiyuan Han ◽

Sandrine Pensec ◽

Cédric Lorthioir ◽

Jacques Jestin ◽

Jean-Michel Guigner ◽

...

Keyword(s):

Hydrogen Bonding ◽

Self Assembly ◽

Functional Materials ◽

Phase Segregation ◽

Building Blocks ◽

Functionalized Polymers ◽

Nanometer Range ◽

One Dimensional ◽

Oil In Water ◽

First Time

Janus cylinders are one-dimensional colloids that have two faces with different compositions and functionalities and are useful as building blocks for advanced functional materials. Such anisotropic objects are difficult to prepare with nanometric dimensions. Here we describe a robust and versatile strategy to form micrometer long Janus nanorods with diameters in the 10-nanometer range, by self-assembly in water of end-functionalized polymers. For the first time, the Janus topology is not a result of the phase segregation of incompatible polymer arms, but is driven by the interactions between unsymmetrical and complementary hydrogen bonded stickers. It is therefore independent of the actual polymers used and works even for compatible polymers. To illustrate their applicative potential, we show that these Janus nanorods can efficiently stabilize oil-in-water emulsions.

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Diverse protein assembly driven by metal and chelating amino acids with selectivity and tunability

Nature Communications ◽

10.1038/s41467-019-13491-w ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 10

Author(s):

Minwoo Yang ◽

Woon Ju Song

Keyword(s):

Amino Acids ◽

Self Assembly ◽

Protein Structures ◽

Functional Materials ◽

Building Blocks ◽

Unnatural Amino Acid ◽

Metal Coordination ◽

Specific Chemical ◽

Natural Building ◽

Kinetics Of

AbstractProteins are versatile natural building blocks with highly complex and multifunctional architectures, and self-assembled protein structures have been created by the introduction of covalent, noncovalent, or metal-coordination bonding. Here, we report the robust, selective, and reversible metal coordination properties of unnatural chelating amino acids as the sufficient and dominant driving force for diverse protein self-assembly. Bipyridine-alanine is genetically incorporated into a D3 homohexamer. Depending on the position of the unnatural amino acid, 1-directional, crystalline and noncrystalline 2-directional, combinatory, and hierarchical architectures are effectively created upon the addition of metal ions. The length and shape of the structures is tunable by altering conditions related to thermodynamics and kinetics of metal-coordination and subsequent reactions. The crystalline 1-directional and 2-directional biomaterials retain their native enzymatic activities with increased thermal stability, suggesting that introducing chelating ligands provides a specific chemical basis to synthesize diverse protein-based functional materials while retaining their native structures and functions.

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Self-assembly of water-soluble silver nanoclusters: superstructure formation and morphological evolution

Nanoscale ◽

10.1039/c7nr06359h ◽

2017 ◽

Vol 9 (48) ◽

pp. 19191-19200 ◽

Cited By ~ 27

Author(s):

Jinglin Shen ◽

Zhi Wang ◽

Di Sun ◽

Guokui Liu ◽

Shiling Yuan ◽

...

Keyword(s):

Self Assembly ◽

Morphological Evolution ◽

Functional Materials ◽

Building Blocks ◽

Water Soluble ◽

Silver Nanoclusters ◽

Efficient Approach ◽

Non Covalent Interactions ◽

Covalent Interactions

Supramolecular self-assembly, based on non-covalent interactions, has been employed as an efficient approach to obtain various functional materials from nanometer-sized building blocks, in particular, [Ag6(mna)6]6−, mna = mercaptonicotinate (Ag6-NC).

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Unveiling the Key Templates in the Self-Assembly of Gigantic Molybdenum Blue Wheels

10.26434/chemrxiv.7496612.v1 ◽

2018 ◽

Author(s):

Weimin Xuan ◽

Robert Pow ◽

Qi Zheng, ◽

Nancy Watfa ◽

De-Liang Long ◽

...

Keyword(s):

Self Assembly ◽

Electrostatic Interactions ◽

Structural Evolution ◽

Functional Materials ◽

Building Blocks ◽

Underlying Mechanism ◽

The Self ◽

Supramolecular Systems ◽

Structure Directing Agent ◽

Molybdenum Blue

Template synthesis is a powerful and useful approach to build a variety of functional materials and complicated supramolecular systems. Systematic study on how templates structurally evolve from basic building blocks and then affect the templated self-assembly is critical to understand the underlying mechanism and gain more guidance for designed assembly but remains challenging. Here we describe the templated self-assembly of a series of gigantic Mo Blue (MB) clusters 1-4 using L-ornithine as structure-directing agent. L-ornithine is essential for the formation of such kind of template⊂host assemblies by providing directional forces of hydrogen bonding and electrostatic interactions. Based on the structural relationship between encapsulated templates of {Mo8} (1), {Mo17} (2) and {Mo36} (4), a plausible pathway of the structural evolution of templates is proposed, thus giving more insight on the templated self-assembly of Mo Blue clusters.

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α-Cyclodextrin-Based Polypseudorotaxane Hydrogels

Materials ◽

10.3390/ma13010133 ◽

2019 ◽

Vol 13 (1) ◽

pp. 133 ◽

Cited By ~ 2

Author(s):

Adrian Domiński ◽

Tomasz Konieczny ◽

Piotr Kurcok

Keyword(s):

Self Assembly ◽

Polymeric Nanoparticles ◽

Functional Materials ◽

Building Blocks ◽

Polymer Chains ◽

Physical Interaction ◽

Wide Range ◽

Potential Applications ◽

Noncovalent Bonds ◽

Significant Attention

Supramolecular hydrogels that are based on inclusion complexes between α-cyclodextrin and (co)polymers have gained significant attention over the last decade. They are formed via dynamic noncovalent bonds, such as host–guest interactions and hydrogen bonds, between various building blocks. In contrast to typical chemical crosslinking (covalent linkages), supramolecular crosslinking is a type of physical interaction that is characterized by great flexibility and it can be used with ease to create a variety of “smart” hydrogels. Supramolecular hydrogels based on the self-assembly of polypseudorotaxanes formed by a polymer chain “guest” and α-cyclodextrin “host” are promising materials for a wide range of applications. α-cyclodextrin-based polypseudorotaxane hydrogels are an attractive platform for engineering novel functional materials due to their excellent biocompatibility, thixotropic nature, and reversible and stimuli-responsiveness properties. The aim of this review is to provide an overview of the current progress in the chemistry and methods of designing and creating α-cyclodextrin-based supramolecular polypseudorotaxane hydrogels. In the described systems, the guests are (co)polymer chains with various architectures or polymeric nanoparticles. The potential applications of such supramolecular hydrogels are also described.

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Shaping colloidal bananas to reveal biaxial, splay-bend nematic, and smectic phases

Science ◽

10.1126/science.abb4536 ◽

2020 ◽

Vol 369 (6506) ◽

pp. 950-955

Author(s):

Carla Fernández-Rico ◽

Massimiliano Chiappini ◽

Taiki Yanagishima ◽

Heidi de Sousa ◽

Dirk G. A. L. Aarts ◽

...

Keyword(s):

Phase Behavior ◽

Self Assembly ◽

Colloidal Particles ◽

Functional Materials ◽

Building Blocks ◽

Develop Model ◽

Smectic Phases ◽

Particle Level ◽

Nematic Phases ◽

The Impact

Understanding the impact of curvature on the self-assembly of elongated microscopic building blocks, such as molecules and proteins, is key to engineering functional materials with predesigned structure. We develop model “banana-shaped” colloidal particles with tunable dimensions and curvature, whose structure and dynamics are accessible at the particle level. By heating initially straight rods made of SU-8 photoresist, we induce a controllable shape deformation that causes the rods to buckle into banana-shaped particles. We elucidate the phase behavior of differently curved colloidal bananas using confocal microscopy. Although highly curved bananas only form isotropic phases, less curved bananas exhibit very rich phase behavior, including biaxial nematic phases, polar and antipolar smectic-like phases, and even the long-predicted, elusive splay-bend nematic phase.

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Self-Assembly of Collagen Building Blocks Guided by Electric Fields

Small ◽

10.1002/smll.201400424 ◽

2014 ◽

Vol 10 (19) ◽

pp. 3876-3879 ◽

Cited By ~ 3

Author(s):

Roberto de la Rica ◽

Ernest Mendoza ◽

Lesley W. Chow ◽

Kristy L. Cloyd ◽

Sergio Bertazzo ◽

...

Keyword(s):

Electric Fields ◽

Self Assembly ◽

Building Blocks

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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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