Monolithic DNApatite: An Elastic Apatite with Sub-Nanometer Scale Organo-Inorganic Structures.

Hydroxyapatite (HA) exhibits outstanding biocompatibility, bioactivity, osteoconductivity, and natural anti-inflammatory properties. Pure HA, ion-doped HA, and HA-polymer composites are investigated, but critical limitations such as brittleness remain; numerous efforts are being made to address them. Herein, the novel self-crystallization of a polymeric single-stranded deoxyribonucleic acid (ssDNA) without additional phosphate ions for synthesizing deoxyribonucleic apatite (DNApatite) is presented.

Pure-Water-Fed Forward-Bias Bipolar Membrane CO Electrolyzer.

Coupling renewable electricity to reduce carbon dioxide (CO) electrochemically into carbon feedstocks offers a promising pathway to produce chemical fuels sustainably. While there has been success in developing materials and theory for CO reduction, the widespread deployment of CO electrolyzers has been hindered by challenges in the reactor design and operational stability due to CO crossover and (bi)carbonate salt precipitation. Herein, we design asymmetrical bipolar membranes assembled into a zero-gap CO electrolyzer fed with pure water, solving both challenges.

Colloidal Synthesis of Ultrathin and Se-Rich VSe Nanobelts as High-Performance Anode Materials for Li-Ion Batteries.

In this study, the one-dimensional (1D) material VSe was successfully synthesized using a colloidal method with VO(acac) and Se powder as precursors in a 1-octadecene solvent. The obtained colloidally synthesized VSe (C-VSe) has an ultrathin nanobelt shape and a 4.5 times higher surface area compared with the bulk VSe, which is synthesized in a solid-state reaction as previously reported.

Peptide-Assembled Single-Chain Atomic Crystal Enhances Pluripotent Stem Cell Differentiation to Neurons.

Nanomaterials hybridized with biological components have widespread applications. among many candidates, peptides are attractive in that their peptide sequences can self-assemble with the surface of target materials with high specificity without perturbing the intrinsic properties of nanomaterials. Here, a 1D hybrid nanomaterial was developed through self-assembly of a designed peptide.

Bioessential Inorganic Molecular Wire-Reinforced 3D-Printed Hydrogel Scaffold for Enhanced Bone Regeneration.

Materials with physicochemical properties and biological activities similar to those of the natural extracellular matrix are in high demand in tissue engineering. In particular, Mo Se inorganic molecular wire (IMW) is a promising material composed of bioessential minerals and possess nanometer-scale diameters, negatively charged surfaces, physical flexibility, and nanotopography characteristics, which are essential for interactions with cell membrane proteins. Here, an implantable 3D Mo Se IMW enhanced gelatin-GMA/silk-GMA hydrogel (IMW-GS hydrogel) is developed for osteogenesis and bone formation, followed by biological evaluations.

Ultrahigh-Porosity MgO Microparticles for Heat-Energy Storage.

Continuous industrial development has increased the demand of energy. Inevitably, the development of energy sources is steadily progressing using various methods. Rather than establishing a new energy source, a system for storing waste heat generated by industry has now been accepted as a useful strategy.

Organic Dispersion of MoSe Single-Chain Atomic Crystals Using Surface Modification Methods.

In this study, single-chain atomic crystals (SCACs), MoSe, which can be uniformly dispersed, with an atomically thin diameter of ∼0.6 nm were modified to disperse in an organic solvent. Various surfactants were chosen to provide steric hindrance to aqueous-dispersed MoSe by modifying the surface of MoSe.

High Breakdown Current Density in Quasi-1D van der Waals Layered Material TaNiSe.

We synthesized ternary composition chalcogenide TaNiSe, a quasi-one-dimensional (Q1D) material with excellent crystallinity. To utilize the excellent electrical conductivity property of TaNiSe, the breakdown current density () according to thickness change through mechanical exfoliation was measured. It was confirmed that as the thickness decreased, the maximum breakdown voltage () increased, and at 18 nm thickness, 35 MA cm of was measured, which was 35 times higher than that of copper, which is commonly used as an interconnect material.

One-dimensional van der Waals stacked p-type crystal TaPtSe for nanoscale electronics.

Recently, ternary transition metal chalcogenides TaXSe (X = Pd or Pt) have attracted great interest as a class of emerging one-dimensional (1D) van der Waals (vdW) materials. In particular, TaPdSe has been actively studied owing to its excellent charge transport properties as an n-type semiconductor and ultralong ballistic phonon transport properties. Compared to subsequent studies on the Pd-containing material, TaPtSe, another member of this class of materials has been considerably less explored despite its promising electrical properties as a p-type semiconductor.

Theoretical Study of Anisotropic Carrier Mobility for Two-Dimensional NbSe Material.

Finding new materials with satisfying all the desired criteria for nanodevices is an extremely difficult work. Here, we introduce a novel NbSe material as a promising candidate, capable of overcoming some physical limitations, such as a suitable band gap, high carrier mobility, and chemical stability. Unlike graphene, it has a noticeable band gap and no dangling bonds at surfaces that deteriorate transport properties, owing to its molecular chain structure.

Bio-essential Inorganic Molecular Nanowires as a Bioactive Muscle Extracellular-Matrix-Mimicking Material.

Many physiochemical properties of the extracellular matrix (ECM) of muscle tissues, such as nanometer scale dimension, nanotopography, negative charge, and elasticity, must be carefully reproduced to fabricate scaffold materials mimicking muscle tissues. Hence, we developed a muscle tissue ECM-mimicking scaffold using MoSI inorganic molecular wires (IMWs). Composed of bio-essential elements and having a nanofibrous structure with a diameter of ∼1 nm and a negative surface charge with high stability, MoSI IMWs are ideal for mimicking natural ECM molecules.

Ta Ni Se : 1D van der Waals Material with Ambipolar Behavior.

In this study, high-purity and centimeter-scale bulk Ta Ni Se crystals are obtained by controlling the growth temperature and stoichiometric ratio between tantalum, nickel, and selenium. It is demonstrated that the bulk Ta Ni Se crystals could be effectively exfoliated into a few chain-scale nanowires through simple mechanical exfoliation and liquid-phase exfoliation. Also, the calculation of electronic band structures confirms that Ta Ni Se is a semiconducting material with a small bandgap.

A study on the bio-applicability of aqueous-dispersed van der Waals 1-D material NbSe using poloxamer.

In this research, dispersion of a new type of one-dimensional inorganic material NbSe, composed of van der Waals bonds, in aqueous solution for bio-application study were studied. To disperse NbSe, which exhibits hydrophobic properties in water, experiments were carried out using a block copolymer (poloxamer) as a dispersant. It was confirmed that PPO, the hydrophobic portion of Poloxamer, was adsorbed onto the surface of NbSe, and PEO, the hydrophilic portion, induced steric hinderance to disperse NbSe to a size of 10 nm or less.

Aqueous Dispersion of One-Dimensional van der Waals Material MoSI with the Charge Type of the Hydrophobic Dispersant Tail.

Aqueous dispersion of van der Waals bonded one-dimensional materials MoSI with hydrophobic surfaces has been studied. The surface charge of the dispersed MoSI is controlled from negative to positive by the charge type of dispersant tail (anionic, SDS and NaDDBS; cationic, CTAB; nonionic, Poloxamer 407), and through this, it is possible to deposit the dispersed MoSI in nanosized by electrophoretic deposition at a desired position. When a flexible device was manufactured by transferring MoSI, it was confirmed that electrical conductivity can be measured in 40% of elongation and more than 1000 times cyclic test.

Edge Defect-Free Anisotropic Two-Dimensional Sheets with Nearly Direct Band Gaps from a True One-Dimensional Van der Waals NbSe Material.

Dangling-bond-free two-dimensional (2D) materials can be isolated from the bulk structures of one-dimensional (1D) van der Waals materials to produce edge-defect-free 2D materials. Conventional 2D materials have dangling bonds on their edges, which act as scattering centers that deteriorate the transport properties of carriers. Highly anisotropic 2D sheets, made of 1D van der Waals NbSe material, have three planar structures depending on the cutting direction of the bulk NbSe crystal.

Indirect-To-Direct Band Gap Transition of One-Dimensional VSe: Theoretical Study with Dispersion Energy Correction.

Recently, we synthesized a one-dimensional (1D) structure of VSe. The 1D VSe resembles another 1D material, NbSe, which is expected to have a direct band gap. To determine the potential applications of this material, we calculated the band structures of 1D and bulk VSe using density functional theory by varying the number of chains and comparing their band structures and electronic properties with those of NbSe.

Design of dispersant for highly concentrated one-dimensional NbSe inorganic molecular chains from bulk crystal.

We determined the optimum dispersant to separate bulk NbSe material into 1D chain units. The NbSe, which had a negative zeta potential (-43.3 mV), showed acidic characteristics and strongly bonded with the amine head of octadecyl amine through a charge transfer (from the amine to Se atoms) reaction.

Thickness-Dependence Electrical Characterization of the One-Dimensional van der Waals TaSe Crystal.

Needle-like single crystalline wires of TaSe were massively synthesized using the chemical vapor transport method. Since the wedged-shaped single TaSe molecular chains were stacked along the b-axis by weak van der Waals interactions, a few layers of TaSe flakes could be easily isolated using a typical mechanical exfoliation method. The exfoliated TaSe flakes had an anisotropic planar structure, and the number of layers could be controlled by a repeated peeling process until a monolayer of TaSe nanoribbon was obtained.

Exceptional Mechanical Properties of Phase-Separation-Free MoSe-Chain-Reinforced Hydrogel Prepared by Polymer Wrapping Process.

As MoSe chain nanowires have dimensions comparable to those of natural hydrogel chains (molecular-level diameters of ∼0.6 nm and lengths of several micrometers) and excellent mechanical strength and flexibility, they have large potential to reinforce hydrogels and improve their mechanical properties. When a MoSe-chain-nanowire-gelatin composite hydrogel is prepared simply by mixing MoSe nanowires with gelatin, phase separation of the MoSe nanowires from the gelatin matrix occurs in the micronetwork, providing only small improvements in their mechanical properties.

Expanded graphene oxide fibers with high strength and increased elongation.

We report the role of chemically expanded graphite in the fabrication of high-performance graphene oxide fibers by wet spinning. X-ray diffraction peak showed that the interplanar distance of the expanded graphene oxide (EGO) fiber was more than that of graphene oxide (GO) fiber due to the expanded graphite. X-ray photon spectroscopy analysis revealed that EGO was more oxidized than GO.

Single-Chain Atomic Crystals as Extracellular Matrix-Mimicking Material with Exceptional Biocompatibility and Bioactivity.

In this study, MoSe single-chain atomic crystals (SCACs) with atomically small chain diameters of ∼0.6 nm, large surface areas, and mechanical flexibility were synthesized and investigated as an extracellular matrix (ECM)-mimicking scaffold material for tissue engineering applications. The proliferation of L-929 and MC3T3-E1 cell lines increased up to 268.

Mechanical exfoliation and electrical characterization of a one-dimensional NbSe atomic crystal.

A novel semiconductor 1D nanomaterial, NbSe, was synthesized on a bulk scale simple vapor transport reaction between niobium and selenium. Needle-like single crystal NbSe contains numerous single NbSe chains linked by van der Waals interactions, and we confirmed that a bundle of chains can be easily separated by mechanical cleavage. The exfoliated NbSe flakes exhibit a quasi-two-dimensional layered structure, and the number of layers can be controlled using the repeated-peeling method.