Alignment and Photopolymerization of Hexa-peri-hexabenzocoronene Derivatives Carrying Diacetylenic Side Chains for Charge-Transporting Application

Morphology and Alignment Transition of Hexabenzocoronene (HBC) Mesogen Films by Bar Coating: Effect of Coating Speed

Films of the discotic liquid crystalline hexabenzocoronene (HBC) derivative, HBC-1,3,5-Ph-C12, were prepared on the quartz substrate by the bar-coating method. Depending on the coating speed, regularly spaced stripes or continuous films were observed. In the former case, columns of the HBC derivatives align more along the stripes, which are perpendicular to the coating direction, whereas in the latter case, columns of the HBC derivatives in the film align more along the coating direction. These distinctive structures are confirmed via polarized optical microscopy (POM), polarized UV-vis spectroscopy, and grazing incidence small-angle X-ray scattering measurements.

Surface supramolecular assemblies tailored by chemical/physical and synergistic stimuli: a scanning tunneling microscopy study

Supramolecular self-assemblies formed by various non-covalent interactions can produce diverse functional networks on solid surfaces. These networks have recently attracted much interest from both fundamental and application points of view. Unlike covalent organic frameworks (COFs), the properties of the assemblies differ from each other depending on the constituent motifs. These various motifs may find diverse applications such as in crystal engineering, surface modification, and molecular electronics. Significantly, these interactions between/among the molecular tectonics are relatively weak and reversible, which makes them responsive to external stimuli. Moreover, for a liquid-solid-interface environment, the dynamic processes are amenable to in situ observation using scanning tunneling microscopy (STM). In the literature, most review articles focus on supramolecular self-assembly interactions. This review summarizes the recent literature in which stimulation sources, including chemical, physical, and their combined stimuli, cooperatively tailor supramolecular assemblies on surfaces. The appropriate design and synthesis of functional molecules that can be integrated on different surfaces permits the use of nanostructured materials and devices for bottom-up nanotechnology. Finally, we discuss synergic effect on materials science.

Hexa-peri-hexabenzocoronene derivatives carrying dovetailed alkyl and diacetylenic side chains: a synthesis, characterization, and polymerization study

A new polymerizable 2,8,14-triphenylhexabenzo[bc,ef,hi,kl,no,qr]coronene (HBC) mesogen bearing alternating dovetailed and linear alkyl chains with a diacetylenic unit were successfully synthesized in this study.

Flow-induced-crystallization: tailoring host-guest supramolecular co-assemblies at the liquid-solid interface

Here, we report that using the method of simply contacting a sample solution droplet with a piece of tissue paper can create a solvent flow (capillary force). During this process, the dynamics and solvent removal can promote the formation and stabilization of a meta-stable linear quasi-crystal composed of p-terphenyl-3,5,3',5'-tetracarboxylic acid (TPTC) molecules, which would otherwise pack into thermodynamically favored random tiling. The tailored quasi-crystal (linear) template allows atop it higher-efficiency accommodation of fullerene molecules (C60) from 40.1% to 97.5%, compared with that obtained in the random-tiling (porous) case. Overall, the result of this study presents an unusual yet remarkably simple strategy for tailoring complex host-guest supramolecular systems at the liquid-solid interface.