Dispersion of Single-Walled Carbon Nanotubes by Aromatic Cyclic Schiff Bases via Non-Covalent Interactions.

One of the challenging issues that hinders the application of single-walled carbon nanotubes (SWCNTs) is the poor solubility and the inevitable formation of bundles. Efforts still need to be made towards solving the problem. Herein, we report a non-covalent strategy to disperse aggregated SWCNTs by aromatic cyclic Schiff bases assisted by ultrasonic techniques.

Single-Shot Laser-Induced Switching of an Exchange Biased Antiferromagnet.

Ultrafast manipulation of magnetic order has challenged the understanding of the fundamental and dynamic properties of magnetic materials. So far single-shot magnetic switching has been limited to ferrimagnetic alloys, multilayers, and designed ferromagnetic (FM) heterostructures. In FM/antiferromagnetic (AFM) bilayers, exchange bias (H) arises from the interfacial exchange coupling between the two layers and reflects the microscopic orientation of the antiferromagnet.

Tunable molecular packing modes H- or J-aggregates in the supramolecular helical nanostructures from an achiral symmetric molecule.

The self-assembly of a -symmetric molecule benzene-1,3,5-tricarboxylate substituted with methyl cinnamate (BTECM) has been investigated by a reprecipitation method in HO and cetyltrimethylammonium bromide (CTAB) aqueous solution, respectively. The nanostructures and characteristics of the assemblies were monitored by UV-Vis spectroscopy, fluorescence (FL) spectroscopy, circular dichroism (CD) spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was found that helical nanostructures were successfully assembled from the achiral molecule BTECM.

Interfacial engineering of ferromagnetism in wafer-scale van der Waals FeGeTe far above room temperature.

Despite recent advances in exfoliated vdW ferromagnets, the widespread application of 2D magnetism requires a Curie temperature (T) above room temperature as well as a stable and controllable magnetic anisotropy. Here we demonstrate a large-scale iron-based vdW material FeGeTe with the T reaching ~530 K. We confirmed the high-temperature ferromagnetism by multiple characterizations.

An enzyme-responsive electrochemical DNA biosensor achieving various dynamic range by using only-one immobilization probe.

Developing a simple and easy-to-operate biosensor with tunable dynamic range would provide enormous opportunities to promote the diagnostic applications. Herein, an enzyme-responsive electrochemical DNA biosensor is developed by using only-one immobilization probe. The immobilization probe was designed with a two-loop hairpin-like structure that contained the mutually independent target recognition and enzyme (EcoRI restriction endonuclease) responsive domains.

Antiferromagnetic spintronics: An overview and outlook.

Over the past few decades, the diversified development of antiferromagnetic spintronics has made antiferromagnets (AFMs) interesting and very useful. After tough challenges, the applications of AFMs in electronic devices have transitioned from focusing on the interface coupling features to achieving the manipulation and detection of AFMs. As AFMs are internally magnetic, taking full use of AFMs for information storage has been the main target of research.

A mitochondria-targeted fluorescent probe for real-time imaging SO/HO.

Studies have shown that changes in the redox state of cells might be closely related to pathological and physiological processes. Sulfur dioxide and hydrogen peroxide, as a significant redox couple in living cells, are endogenously produced by cells. Here, we report a long-wavelength fluorescent probe to reversibly monitor sulfur dioxide and hydrogen peroxide.

Discrete π-Stacks from Self-Assembled Perylenediimide Analogues.

The formation of well-defined finite-sized aggregates represents an attractive goal in supramolecular chemistry. In particular, construction of discrete π-stacked dye assemblies remains a challenge. Reported here is the design and synthesis of a novel type of discrete π-stacked aggregate from two comparable perylenediimide (PDI) dyads (PEP and PBP).

Synthesis and Supramolecular Assembly of a Terrylene Diimide Derivative Decorated With Long Branched Alkyl Chains.

Terrylene diimide derivatives are pigments for dyes and optoelectric devices. A terrylene diimide derivative N,N'-di(1-undecyldodecyl)terrylene-3,4:11,12-tetracarboxdiimide (DUO-TDI) decorated with long branched alkyl chains on both imide nitrogen atoms was designed and synthesized. The supramolecular assembly behaviors of DUO-TDI in solution and at the liquid-solid interface were both investigated.

Solvent-Induced Supramolecular Assembly of a Peptide-Tetrathiophene-Peptide Conjugate.

The assembly of a peptide-tetrathiophene-peptide (PTP) conjugate has been investigated in mixed solvents, which has different polarities by changing the solvent proportions. It was found that PTP can form fibers in THF/hexane solutions with 40-80%v of hexane. The fibers were stable and did not change on time.

Switchable circularly polarized luminescence from a photoacid co-assembled organic nanotube.

Materials with circularly polarized luminescence (CPL) are currently attracting great interest in view of their potential applications. Here, we reported self-assembled organic nanotubes with switchable CPL performance. A photoacid, 8-hydroxy-1,3,6-pyrenetrisulfonate (HPTS), was co-assembled with an amino-terminated dialkyl glutamide (LG or DG) in mixed solvents of DMF and water.

Supramolecular Self-Assembly of Perylene Bisimide Derivatives Assisted by Various Groups.

Anthra[2,1,9-def:6,5,10-d'e'f']diisoquinoline-1,3,8,10(2H,9H)-tetraone, namely, perylene bisimides (PBIs), belong to n-type organic semiconductors and possess potential applications in optoelectronic devices. The properties/performance of fabricated nanostructures/devices could be greatly influenced by both molecular structures of PBI building blocks and corresponding arrangement in assembled nanostructures. Many efforts have been made to modify the PBI core and then investigate the nanostructures and properties.

Selective Ortho-π-Extension of Perylene Diimides for Rylene Dyes.

A range of ortho-π-extended PDI derivatives are straightforwardly synthesized in good yields through highly regioselective heteroannulations of ortho-alkynyl-substituted PDI derivatives with sulfur, selenium, or nitrogen nucleophiles. Successful synthesis of pyrrole-fused rylene dyes by using primary amines as nucleophiles indicates the great synthetic potential of this facile annulation route. Further opto-electrochemical study of these novel thiophene-, selenophene-, and pyrrole-fused PDIs suggests that effective π-conjugation enlargement combined with distortion of the perylene core renders these PDI derivatives tunable and desirable physical properties.

Design and Fabrication of Full Wheatstone-Bridge-Based Angular GMR Sensors.

Since the discovery of the giant magnetoresistive (GMR) effect, GMR sensors have gained much attention in last decades due to their high sensitivity, small size, and low cost. The full Wheatstone-bridge-based GMR sensor is most useful in terms of the application point of view. However, its manufacturing process is usually complex.

Amorphous Porous Organic Polymers Based on Schiff-Base Chemistry for Highly Efficient Iodine Capture.

Porous organic polymers (POPs) have been considered as prominent adsorbents for volatile iodine. So far, both crystalline and amorphous POPs have accomplished excellent iodine capture capability. Considering the difficulty and challenges in preparing perfect crystalline POPs, more explorations into developing versatile amorphous POPs are needed.

Role of halogenhalogen interactions in the 2D crystallization of n-semiconductors at the liquid-solid interface.

The impact of halogenhalogen interactions on the 2D crystallization of n-semiconductors was investigated. The 2D nanostructures and chirality could be altered by the introduction of bromine atoms for both single component and binary surface assembly supported by STM and simulation results.

Impact of Linear Alkyl Length on the Assembly of Twisted Perylene Bisimides: From Molecular Arrangement to Nanostructures.

The effect of the length of linear alkyl chains substituted at imine positions on the assembly of tetrachlorinated perylene bisimides (1: PBI with -C H ; 2: PBI with -C H ) has been investigated. Solvent-induced assembly was performed in solutions of THF and methanol with varying volume ratios. Morphological (SEM, AFM, and TEM) and spectral (UV/Vis, fluorescence, FTIR, and XRD) methods were used to characterize the assembled nanostructures and the molecular arrangement in the aggregates.

Role of intrinsic hydrogen bonds in the assembly of perylene imide derivatives in solution and at the liquid-solid interface.

The impact of hydrogen bond formation on the supramolecular assembly of two perylene imide derivatives (PMAMI and PDINH) was systematically investigated in solution and at the liquid-solid interface. PDINH has intrinsic hydrogen bond sites, but this is not the case for PMAMI. The solution assembly was explored by morphological methods (SEM, AFM, TEM and cryo-TEM) and spectral characterization (UV-vis, FL, XRD, and FTIR spectra).

Two-Dimensional Crystallization of Rylene Diimide Based n-Type Semiconductors Tuned by the Dimensions of the Aromatic Core at the Liquid-Solid Interface.

The investigation of semiconductors at the surface provides opportunities to observe and understand the mechanism of molecular interaction for the design of semiconductors so that organic electronics with good performance can be built. Herein, the 2D crystallization of rylene diimide based n-type semiconductors (i.e.

Co-assembly of donor and acceptor towards organogels tuned by charge transfer interaction strength.

Co-assembly of n-type semiconductors NDI and PDI with p-type pyrene derivatives resulted in the formation of stable organogels, which was induced by the strong charge transfer (CT) interactions between acceptors and donors in chloroform. The dimension size of the aromatic core from the acceptors was found to have a significant impact on the organogels. The width of the fibers from CT gels with NDI is about twice that from gels with PDI.

2,5,8,11-Tetraalkenyl Perylene Bisimides: Direct Regioselective Synthesis and Enhanced π-π Stacking Interaction.

A series of 2,5,8,11-tetraalkenyl perylene bisimide (PBI) derivatives were synthesized through Ru(II)- or Rh(III)-catalyzed regio- and steroselective oxidative C-H olefination in one step. The optical electronic and self-assembly of the 2,5,8,11-substituted PBIs were investigated, which showed great potential in optoelectronic applications.

Nano-mechanical characterization of disassembling amyloid fibrils using the Peak Force QNM method.

The comprehensive understanding of disassembly mechanism of amyloid fibrils requires nano-scale characterization of the mechanical properties of amyloid fibrils during the disassembly process. In this work, gemini surfactant C C C Br micelles were used as a probe to disassemble Aβ(1-40) fibrils. The microstructure evolution and nano-mechanical properties of Aβ(1-40) fibrils during the disassembly process were systematically investigated by the Peak Force Quantitative Nano-mechanical (PF-QNM) technique.

The Assembling of Poly (3-Octyl-Thiophene) on CVD Grown Single Layer Graphene.

The interface between organic semiconductor and graphene electrode, especially the structure of the first few molecular layers at the interface, is crucial for the device properties such as the charge transport in organic field effect transistors. In this work, we have used scanning tunneling microscopy to investigate the poly (3-octyl-thiophene) (P3OT)-graphene interface. Our results reveal the dynamic assembling of P3OT on single layer graphene.

Tetrapeptide-coumarin conjugate 3D networks based on hydrogen-bonded charge transfer complexes: gel formation and dye release.

Oligopeptide-based derivatives are important synthons for bio-based functional materials. In this article, a Gly-(L-Val)-Gly-(L-Val)-coumarin (GVGV-Cou) conjugate was synthesized, which forms 3D networks in ethanol. The gel nanostructures were characterized by UV-vis spectroscopy, FT-IR spectroscopy, X-ray diffraction (XRD), SEM and TEM.

Side-functionalized two-dimensional polymers synthesized via on-surface Schiff-base coupling.

An imine-based 2D polymer side-functionalized with o-hydroxyl group was designed in regard to its potential ability to serve as a chelating agent and synthesized on a highly oriented pyrolytic graphite surface with a relatively low annealing temperature. When annealed to a higher temperature the o-hydroxyl group reacts further with the imine group, leading to the formation of oxazoline, which causes significant distortion to the network. The formation of oxazoline was further confirmed by ATR-FTIR.