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A practical and green approach to the development of color-tunable luminescent composites through in situ solvent-free synthesis of carbon dots on layered inorganic compounds is reported.

Potential applications of functional liquid crystals such as biosensors strongly rely on control of the molecular orientation at interfaces. However, little knowledge regarding detailed molecular a...

Thermotropic liquid crystals having tripeptide moieties are reported. A series of peptide chains including arginine-glycine-aspartic acid (RGD), glycine-glycine-aspartic acid (GGD), and triglycine ...

We here report a new approach to develop self-healing shape memory supramolecular liquid-crystalline (LC) networks through self-assembly of molecular building blocks via combination of hydrogen bonding and coordination bonding. We have designed and synthesized supramolecular LC polymers and networks based on the complexation of a forklike mesogenic ligand with Ag+ ions and carboxylic acids. Unidirectionally aligned fibers and free-standing films forming layered LC nanostructures have been obtained for the supramolecular LC networks. We have found that hybrid supramolecular LC networks formed through metal–ligand interactions and hydrogen bonding exhibit both self-healing properties and shape memory functions, while hydrogen-bonded LC networks only show self-healing properties. The combination of hydrogen bonds and metal–ligand interactions allows the tuning of intermolecular interactions and self-assembled structures, leading to the formation of the dynamic supramolecular LC materials. The new material design presented here has potential for the development of smart LC materials and functional LC membranes with tunable responsiveness., New supramolecular hybrid liquid-crystalline networks exhibiting self-healing and shape memory properties are developed by self-assembly of small components through hydrogen bonding interactions and coordination bonding.

Novel liquid-crystalline N,N′-diarylsquaramides 1a and 1b were designed and synthesized, and their properties were elucidated. The squaramides exhibited thermotropic columnar liquid-crystalline phases at low temperature including room temperature. X-ray crystallographic analysis of methoxy derivative 1c showed the self-assembly of face-to-faced dimer through π-π interaction.

Supramolecular self-assembly of 24 forklike mesogenic ligands and 12 transition metal ions leads to formation of giant spherical coordination complexes that exhibit liquid-crystalline (LC) phases. Self-healing LC supramolecular gels have also been obtained by introduction of these LC nanostructured supramolecular giant spherical complexes into dynamic covalent networks formed by cross-linkers and bifunctional polymers. The giant spherical structures of the Pd(II) complexes with 72 rodlike moieties on the periphery have been characterized by NMR, diffusion-ordered NMR spectroscopy, and mass spectrometry. These complexes are stable and exhibit lyotropic LC behavior, while the mesogenic ligands show thermotropic LC properties. The self-assembled LC structures of the spherical complexes can be tuned by the length of the rodlike moieties.

Dendritic molecules having several rigid-rod moieties can be applied to induce liquid crystallinity for a variety of non-mesomorphic functional molecules such as metal complexes, nanoparticles, fullerenes and π-conjugated molecules when these dendritic molecules are covalently bonded to those non-mesomorphic molecules. These complex molecules are called supermolecular liquid crystals. Due to the cooperation of several mesogenic moieties, these dendritic molecules exhibit very stable liquid-crystalline (LC) phases. We have used fork-shaped LC dendrons having two or three rigid-rod moieties to induce liquid crystallinity for functional molecules such as interlocked molecules and π-conjugated molecules. In these fork-like molecules, the rigid-rod cores are attached to the 3,4,5-position of the phenyl moieties through flexible spacer, and these molecules are bonded to functional molecules through the 1-position. They basically form smectic LC phases, which induce the layered arrangement of functional moieties. Here we report on a new family of fork-like mesogens containing a hydrogen bonding moiety or an ionic group. They are designed to build supramolecular materials.

Since the discovery of the liquid-crystalline state in 1888, liquid crystal science has made great advances through fusion with various technologies and disciplines. Recently, new molecular design strategies and new self-assembled structures have been developed as a result of the progress made in synthetic procedures and characterization techniques. Since these liquid crystals exhibit new functions and properties derived from their nanostructures and alignment, a variety of new functions for liquid crystals, such as transport for energy applications, separation for environmental applications, chromism, sensing, electrooptical effects, actuation, and templating have been proposed. This Review presents recent advances of liquid crystals that should contribute to the next generation of materials.