Density Multiplication of Highly Periodic Sub-5 nm Supramolecular Dendrimer Cylinders on Block Copolymer Lamellar-Assisted High-Resolution Patterns.

Density multiplication in nanopatterning is one of the most efficient techniques for increasing the resolution of the inherent patterns. Thus far, most of the density multiplication techniques integrate bottom-up (or top-down) patterning onto guide patterns prepared by the top-down approach. Although the bottom-up approach exhibits several advantages of cost-effectiveness and high resolution, very few studies have reported bottom-up patterning within a bottom-up template.

Wafer-Scale Unidirectional Alignment of Supramolecular Columns on Faceted Surfaces.

The long-range alignment of supramolecular structures must be engineered as a first step toward advanced nanopatterning processes aimed at miniaturizing features to dimensions below 5 nm. This study introduces a facile method of directing the orientation of supramolecular columns over wafer-scale areas using faceted surfaces. Supramolecular columns with features on the sub-5 nm scale were highly aligned in a direction orthogonal to that of the facet patterning on unidirectional and nanoscopic faceted surface patterns.

Direct Growth of Highly Conductive Large-Area Stretchable Graphene.

The direct synthesis of inherently defect-free, large-area graphene on flexible substrates is a key technology for soft electronic devices. In the present work, in situ plasma-assisted thermal chemical vapor deposition is implemented in order to synthesize 4 in. diameter high-quality graphene directly on 10 nm thick Ti-buffered substrates at 100 °C.

Large-Area Alignment of Supramolecular Columns by Photothermal Laser Writing.

Controlling the orientation of highly periodic supramolecular structures of small feature size (<5 nm) is the first step for potential applications in optoelectronics, membranes, and template synthesis. A new method, namely, laser photothermal writing, is introduced to direct the orientation of supramolecular columns over a large area. Supramolecular columns consisting of taper-shaped molecules with long aliphatic tail groups are aligned by a thermal gradient, which is induced by exposing a near-infrared laser beam to a graphene photothermal conversion layer.

Hierarchical Self-Assembly of Perylene Diimide (PDI) Crystals.

Controlling molecular self-assembly of organic semiconductors is a key factor in enhancing the performance of organic electronics and optoelectronics. However, unlike various p-type organic semiconductors, it has proven elusive to control molecular self-assembly with about tens of nm dimensions using n-type organic semiconductors including perylene diimide (PDI), which is the most promising alternative to fullerene derivatives, without using an additional synthetic method or additives, thus far. Here, we developed a simple self-assembling method for the hierarchical self-assembly of PDI crystals with nanometer-to-micrometer scale features using pristine PDI-C8 without using an additional synthetic method or additive.

Sculpted grain boundaries in soft crystals.

Engineering the grain boundaries of crystalline materials represents an enduring challenge, particularly in the case of soft materials. Grain boundaries, however, can provide preferential sites for chemical reactions, adsorption processes, nucleation of phase transitions, and mechanical transformations. In this work, "soft heteroepitaxy" is used to exert precise control over the lattice orientation of three-dimensional liquid crystalline soft crystals, thereby granting the ability to sculpt the grain boundaries between them.

Ultra-dense (~20 Tdot/in) nanoparticle array from an ordered supramolecular dendrimer containing a metal precursor.

The fabrication of an ultra-dense, highly periodic nanoparticle array from a soft template is one of the most important issues in the fields of material science and nanotechnology. To date, block copolymer (BCP) structures have been primarily used as templates for fabricating highly periodic nanoparticle arrays with high areal densities. Herein, we demonstrate for the first time the use of a supramolecular dendrimer assembly for the formation of a highly ordered nanoparticle array with a high areal density of ~20 Tdot/in, four times larger than that of the currently reported BCP-based nanoparticle arrays.

Perfection in Nucleation and Growth of Blue-Phase Single Crystals: Small Free-Energy Required to Self-Assemble at Specific Lattice Orientation.

Chemically patterned surfaces can be used to selectively stabilize blue phases as macroscopic single crystals with a prescribed lattice orientation. By tailoring the interfacial free energy through the pattern characteristics, it is possible to set, with nanoscale precision, the optimal conditions to induce spontaneously blue-phase crystal nucleation on the patterned substrate where a uniform, defect-free, blue-phase single crystal is finally formed in a matter of seconds. The chemical patterns taken into consideration in this work are made up of alternated stripelike regions of homeotropic and planar anchoring.

Ultrasmall Grained Pd Nanopattern H Sensor.

Precise control of the size and interfaces of Pd grains is very important for designing a high-performance H sensing channel because the transition of the Pd phase from α to β occurs through units of single grains. However, unfortunately, the grain controllability of previous approaches has been limited to grains exceeding 10 nm in size and simple macroscopic channel structures have only shown monotonic response behavior for a wide concentration range of H. In this work, for the first time, we found that Pd channels that are precisely grain-controlled show very different H sensing behavior.

Rational Design of Aminopolymer for Selective Discrimination of Acidic Air Pollutants.

Strong acidic gases such as CO, SO, and NO are harsh air pollutants with major human health threatening factors, and as such, developing new tools to monitor and to quickly sense these gases is critically required. However, it is difficult to selectively detect the acidic air pollutants with single channel material due to the similar chemistry shared by acidic molecules. In this work, three acidic gases (i.

Long-range single domain array of a 5 nm pattern of supramolecules via solvent annealing in a double-sandwich cell.

In nanotechnology and microelectronics research, the generation of an ultradense, single-grain nanostructure with a long-range lateral order is challenging. In this paper, we report upon a new solvent-annealing method using a double-sandwich confinement to promote the formation of a large-area, single-domain array (>0.3 × 0.

One dimensional building blocks for molecular separation: laminated graphitic nanoribbons.

Herein, a new carbon-based graphitic membrane composed of laminated graphitic nanoribbons with a nanometer-scale width and micrometer-scale length, the graphitic nanoribbon membrane, is reported. Compared to the existing graphitic membranes, such as those composed of graphene oxide and carbon nanotubes, the developed membrane exhibits several unique characteristics in pressure-driven systems. First, the short diffusion length through its interlayer and the free volume of its stacked nanoribbons result in high solvent flux regardless of solvent polarity (water: 25-250 L m h bar; toluene: ∼975 L m h bar; hexane: ∼240 L m h bar).

Bio-information scanning technology using an optical pick-up head.

We have developed a low cost and a highly compact bio-chip detection technology by modifying a commercially available optical pick-up head for CD/DVD. The highly parallel and miniaturized hybridization assays are addressed by the fluorescence emitted by the DNA-chip using the optical pick-up head. The gap between the objective lens and the bio-chip is regulated by the focus servo during the detection of the fluorescence signal.