13,323 results match your criteria Nano Letters [Journal]


Spatial mapping of local density variations in two-dimensional electron systems using scanning photoluminescence.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

We have developed a scanning photoluminescence technique that can directly map out the local two-dimensional electron densities with a relative accuracy of ~2.2×10 cm. The validity of this approach is confirmed by the observation of the expected density gradient in a high-quality GaAs quantum well sample that was not rotated during the molecular beam epitaxy of its spacer layer. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05047DOI Listing
February 2019

Generalized On-demand Production of Nanoparticle Monolayers on Arbitrary Solid Surfaces via Capillarity-mediated Inverse Transfer.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

Century-old Langmuir monolayer deposition still represents the most convenient approach to the production of monolayers of colloidal nanoparticles on solid substrates for practical biological and chemical sensing applications. However, this approach simply yields arbitrarily-shaped large monolayers on a flat surface, and is strongly limited by substrate topography and interfacial energy. Here we describe a generalized and facile method of rapidly producing uniform monolayers of various colloidal nanoparticles on arbitrary solid substrates by using an ordinary capillary tube. Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00248DOI Listing
February 2019

Atomic-scale origin of enhanced ionic conductivity at crystal defects.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

In oxide materials, the presence of dislocations often strongly affects the properties of thin film and multilayer devices. Although it was reported that ionic conduction can be enhanced by introducing dislocations in ionic conductors, the underlying mechanism of such enhancement remains unclear. Here we analyzed the ionic conduction enhancement in an yttria-stabilized zirconia (YSZ) single edge dislocation from structural point of view, using atomic resolution scanning transmission electron microscopy (STEM). Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00506DOI Listing
February 2019

Visualization of Local Conductance in MoS/WSe Heterostructure Transistors.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

The vertical stacking of van der Waals (vdW) materials introduces a new degree of freedom to the research of two-dimensional (2D) systems. The interlayer coupling strongly influences the band structure of the heterostructures, resulting in novel properties that can be utilized for electronic and optoelectronic applications. Based on microwave microscopy studies, we report quantitative electrical imaging on gated molybdenum disulfide (MoS)/tungsten diselenide (WSe) heterostructure devices, which exhibit an intriguing anti-ambipolar effect in the transfer characteristics. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05159DOI Listing
February 2019

Stepwise ligand-induced self-assembly for facile fabrication of nanodiamond-gold nanoparticle dimers via non-covalent biotin-streptavidin interactions.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

Nanodiamond-gold nanoparticle (ND-AuNP) dimers constitute a potent tool for controlled thermal heating of biological systems on the nanoscale, by combining a local light-induced heat source with a sensitive local thermometer. Unfortunately, previous solution-based strategies to build ND-AuNP conjugates resulted in large nanoclusters or a broad population of multimers with limited separation efficiency. Here, we describe a new strategy to synthesize discrete ND-AuNP dimers via the synthesis of biotin-labeled DNA-AuNPs through thiol chemistry and its immobilization onto the magnetic bead (MB) surface, followed by reacting with streptavidin-labeled NDs. Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00113DOI Listing
February 2019

Dimension Engineering of High-Quality InAs Nanostructures on a Wafer-Scale.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

Low-dimensional narrow bandgap III-V semiconductors are key building blocks for the next generation of high-performance nano-electronics, nano-photonics and quantum devices. To realize these various applications, it requires an efficient methodology that enables the material dimensional control during the synthesis process and the mass production of these materials with perfect crystallinity, reproducibility, low cost and outstanding optoelectronic properties. However, despite advances in one- and two-dimensional narrow bandgap III-V semiconductors synthesis, the progress towards reliable methods that can satisfy all of these requirements has been limited. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04561DOI Listing
February 2019

Phonon Polariton-assisted Infrared Nanoimaging of Local Strain in Hexagonal Boron Nitride.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

Key Laboratory of Artificial Structures and Quantum Control (Ministry of Education), School of Physics and Astronomy , Shanghai Jiao Tong University , Shanghai 200240 , China.

Strain plays an important role in condensed matter physics and materials science because it can strongly modify the mechanical, electrical, and optical properties of a material and even induce a structural phase transition. Strain effects are especially interesting in atomically thin two-dimensional (2D) materials, where unusually large strain can be achieved without breaking them. Measuring the strain distribution in 2D materials at the nanometer scale is therefore greatly important but is extremely challenging experimentally. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.8b05166
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http://dx.doi.org/10.1021/acs.nanolett.8b05166DOI Listing
February 2019
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Epitaxial van der Waals Contacts between Transition-metal Dichalcogenide Monolayer Polymorphs.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

We have achieved heteroepitaxial stacking of a van der Waals ( vdW) monolayer metal, 1T'-WTe and semiconductor, 2H-WSe, in which a distinctively low contact barrier was established across a clean epitaxial vdW gap. Our epitaxial 1T'-WTe films were identified as a semimetal by low temperature transport, and showed the robust breakdown current density of 5.0 x 10 A/cm. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.8b04869
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http://dx.doi.org/10.1021/acs.nanolett.8b04869DOI Listing
February 2019
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Hyperbolic Meta-Antennas Enable Full Control of Scattering and Absorption of Light.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

We introduce a novel concept of hybrid metal-dielectric meta-antenna supporting type II hyperbolic dispersion, which enables a full control of absorption and scattering of light in the visible/near-infrared spectral range. This ability lies on the different nature of the hyperbolic Bloch-like modes excited within the meta-antenna. The experimental evidence is corroborated by a comprehensive theoretical study. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04841DOI Listing
February 2019

Cancer cells invade confined microchannels via a self-directed mesenchymal-to-amoeboid transition.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Cancer cell invasion through physical barriers in the extracellular matrix (ECM) requires a complex synergy of traction force against the ECM, mechanosensitive feedback, and subsequent cytoskeletal rearrangement. PDMS microchannels were used to investigate the transition from mesenchymal to amoeboid invasion in cancer cells. Migration was faster in narrow 3 μm-wide channels than in wider 10 μm channels, even in the absence of cell-binding ECM proteins. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04720DOI Listing
February 2019

Antibody-Armed Platelets for the Regenerative Targeting of Endogenous Stem Cells.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Department of Cardiology , The First Affiliated Hospital of Zhengzhou University , Zhengzhou , Henan 450052 , China.

Stem cell therapies have shown promise in treating acute and chronic ischemic heart disease. However, current therapies are limited by the low retention and poor integration of injected cells in the injured tissue. Taking advantage of the natural infarct-homing ability of platelets, we engineered CD34 antibody-linked platelets (P-CD34) to capture circulating CD34-positive endogenous stem cells and direct them to the injured heart. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04970DOI Listing
February 2019

Engineered MSC/Nanomedicine Spheroid as an Active Drug Delivery Platform for Combinational Glioblastoma Therapy.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Mesenchymal stem cell (MSC) has been increasingly applied to cancer therapy because of its tumor-tropic capability. However, short retention at target tissue and limited payload option hinder the progress of MSC-based cancer therapy. Herein, we proposed a hybrid spheroid/nanomedicine system, comprising MSC spheroid entrapping drug-loaded nanocomposite to address these limitations. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04697DOI Listing
February 2019

Pointing in the Right Direction: Controlling the Orientation of Proteins on Nanoparticles Improves Targeting Efficiency.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Protein-conjugated nanoparticles have the potential to precisely deliver therapeutics to target sites in the body by specifically binding to cell surface receptors. To maximize targeting efficiency, the three-dimensional presentation of ligands towards these receptors is crucial. Herein, we demonstrate significantly enhanced targeting of nanoparticles to cancer cells by controlling the protein orientation on the nanoparticle surface. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04916DOI Listing
February 2019

Tumor Microenvironment-Responsive Cu(OH)PO Nanocrystals for Selective and Controllable Radiosentization via the X-ray-Triggered Fenton-like Reaction.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety , Institute of High Energy Physics, Chinese Academy of Sciences , Beijing 100049 , China.

Traditional radiotherapy can induce injury to the normal tissue around the tumor, so the development of novel radiosensitizer with high selectivity and controllability that can lead to more effective and reliable radiotherapy is highly desirable. Herein, a new smart radiosensitizer based on Cu(OH)PO nanocrystals that can simultaneously respond to endogenous stimulus (HO) and exogenous stimulus (X-ray) is reported. First, Cu(OH)PO nanocrystals can generate Cu sites under X-ray irradiation through X-ray-induced photoelectron transfer process. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04763DOI Listing
February 2019

Quantitative mapping of oxidative stress response to lithium cobalt oxide nanoparticles in single cells using multiplexed in situ gene expression analysis.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Engineered nanoparticles (NPs) can negatively impact biological systems through induced generation of reactive oxygen species (ROS). Over-produced ROS cause biochemical damage and hence need to be effectively buffered by a sophisticated cellular oxidative stress response system. How this complex cellular system, which consists of multiple enzymes, responds to NP-induced ROS is largely unknown. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05172DOI Listing
February 2019

Deterministic Quantum Emitter Formation in Hexagonal Boron Nitride via Controlled Edge Creation.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

Department of Physics; Material Science Institute; Center for Optical, Molecular, and Quantum Science , University of Oregon , Eugene , Oregon 97403 , United States.

Quantum emitters (QEs) in 2D hexagonal boron nitride (hBN) are extremely bright and are stable at high temperature and under harsh chemical conditions. Because they reside within an atomically thin 2D material, these QEs have a unique potential to couple strongly to hybrid optoelectromechanical and quantum devices. However, this potential for coupling has been underexplored because of challenges in nanofabrication and patterning of hBN QEs. Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00357DOI Listing
February 2019

Photodynamic Therapy with Liposomes Encapsulating Photosensitizers with Aggregation-Induced Emission.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Colloid and Interface Science , Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190 , China.

As a noninvasive treatment, photodynamic therapy (PDT) is a promising strategy against tumors. It is based on photosensitizer (PS)-induced phototoxicity after irradiation. However, most clinically approved PSs will be widely distributed in normal tissues, especially in the skin, where they will induce phototoxicity on exposure to light. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04875DOI Listing
February 2019

In Situ Nanoscale Redox Mapping Using Tip-Enhanced Raman Spectroscopy.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.

Electrochemical atomic force microscopy tip-enhanced Raman spectroscopy (EC-AFM-TERS) was used for the first time to spatially resolve local heterogeneity in redox behavior on an electrode surface in situ and at the nanoscale. A structurally well-defined Au(111) nanoplate located on a polycrystalline ITO substrate was studied to examine nanoscale redox contrast across the two electrode materials. By monitoring the TERS intensity of adsorbed Nile Blue (NB) molecules on the electrode surface, TERS maps were acquired with different applied potentials. Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00313DOI Listing
February 2019

Golden Exosomes Selectively Target Brain Pathologies in Neurodegenerative and Neurodevelopmental Disorders.

Nano Lett 2019 Feb 14. Epub 2019 Feb 14.

Exosomes, nano-vesicles that are secreted by different cell types, enable intercellular communication at local or distant sites. Though they have been found to cross the blood brain barrier, their migration and homing abilities within the brain remain unstudied. We have recently developed a method for longitudinal and quantitative in vivo neuroimaging of exosomes, based on the superior visualization abilities of classical X-ray computed tomography (CT), combined with gold nanoparticles as labeling agents. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04148DOI Listing
February 2019
2 Reads

Enhancement of Ultrahigh Rate Chargeability by Interfacial Nanodot BaTiO Treatment on LiCoO Cathode Thin Film Batteries.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Laboratory for Materials and Structures , Tokyo Institute of Technology , Yokohama 226-8503 , Japan.

Nanodot BaTiO supported LiCoO cathode thin films can dramatically improve high-rate chargeability and cyclability. The prepared BaTiO nanodot is <3 nm in height and 35 nm in diameter, and its coverage is <5%. Supported by high dielectric constant materials on the surface of cathode materials, Li ion (Li) can intercalate through robust Li paths around the triple-phase interface consisting of the dielectric, cathode, and electrolyte. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04690DOI Listing
February 2019
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Ultrasensitive Monolayer MoS Field-Effect Transistor Based DNA Sensors for Screening of Down Syndrome.

Nano Lett 2019 Feb 13. Epub 2019 Feb 13.

Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics , Peking University , Beijing 100871 , China.

Field-effect transistor (FET) biosensors based on low-dimensional materials present the advantages of low cost, high speed, small size, and excellent compatibility with integrated circuits (ICs). In this work, we fabricated highly sensitive FET-based DNA biosensors based on chemical vapor deposition (CVD)-grown monolayer MoS films in batches and explored their application in noninvasive prenatal testing (NIPT) for trisomy 21 syndrome. Specifically, MoS was functionalized with gold nanoparticles (Au NPs) of an optimized size and at an ideal density, and then, probe DNAs for the specific capture of target DNAs were immobilized on the nanoparticles. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.8b03818
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http://dx.doi.org/10.1021/acs.nanolett.8b03818DOI Listing
February 2019
2 Reads

Thermoelectric Performance of 2D Tellurium with Accumulation Contacts.

Nano Lett 2019 Feb 12. Epub 2019 Feb 12.

Tellurium (Te) is an intrinsically p-type doped narrow bandgap semiconductor with excellent electrical conductivity and low thermal conductivity. Bulk trigonal Te has been theoretically predicted and experimentally demonstrated to be an outstanding thermoelectric material with high value of thermoelectric figure-of-merit ZT. In view of the recent progress in developing synthesis route of two-dimensional (2D) tellurium thin films as well as the growing trend of exploiting nanostructures as thermoelectric devices, here for the first time we report excellent thermoelectric performance of tellurium nanofilms, with room temperature power factor of 31. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05144DOI Listing
February 2019
3 Reads

Isotope Effect in Bilayer WSe.

Nano Lett 2019 Feb 12. Epub 2019 Feb 12.

Isotopes of an element have the same electron number but differ in neutron number and atomic mass. However, due to the thickness-dependent properties in MX (M=Mo, W; X=S, Se, Te) transition metal dichalcogenides (TMDs), the isotopic effect in atomically-thin TMDs still remains unclear especially for phonon-assisted indirect excitonic transitions. Here, we report the first observation of the isotope effect on the electronic and vibrational properties of a TMD material, using naturally abundant WSe and isotopically pure bilayer WSe single crystals over a temperature range of 4. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04269DOI Listing
February 2019
2 Reads

Observation of Uncompensated Bound Charges at Improper Ferroelectric Domain Walls.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

Department of Materials , ETH Zurich , Vladimir-Prelog-Weg 4 , 8093 Zurich , Switzerland.

Low-temperature electrostatic force microscopy (EFM) is used to probe unconventional domain walls in the improper ferroelectric semiconductor ErCaMnO down to cryogenic temperatures. The low-temperature EFM maps reveal pronounced electric far fields generated by partially uncompensated domain-wall bound charges. Positively and negatively charged walls display qualitatively different fields as a function of temperature, which we explain based on different screening mechanisms and the corresponding relaxation time of the mobile carriers. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04608DOI Listing
February 2019

Electric-Field-Tunable Growth of Organic Semiconductor Crystals on Graphene.

Nano Lett 2019 Feb 18. Epub 2019 Feb 18.

Department of Chemical Engineering , Pohang University of Science and Technology , Pohang 37673 , Korea.

Growth of organic semiconductor thin films on a two-dimensional template is affected by its properties and is not well understood. This growth process dictates a thin film's final morphology and crystal structure and is controlled by the interactions between ad-molecules and the template. Here, we report that the template's charge density determines the tuning of such interactions. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04764DOI Listing
February 2019
1 Read

Layer-Dependent Electronic Structure of Atomically Resolved Two-Dimensional Gallium Selenide Telluride.

Nano Lett 2019 Feb 15. Epub 2019 Feb 15.

Department of Physics , University of California at Berkeley , Berkeley , California 94720 , United States.

Alloying two-dimensional (2D) semiconductors provides a powerful method to tune their physical properties, especially those relevant to optoelectronic applications. However, as the crystal structure becomes more complex, it becomes increasingly difficult to accurately correlate response characteristics to detailed atomic structure. We investigate, via annular dark-field scanning transmission electron microscopy, electron energy loss spectroscopy, and second harmonic generation, the layered III-VI alloy GaSeTe as a function of layer number. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04802DOI Listing
February 2019
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Grooved Dayem Nanobridges as Building Blocks of High-Performance YBaCuO SQUID Magnetometers.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience - MC2 , Chalmers University of Technology , Gothenburg SE-41296 , Sweden.

We present noise measurements performed on a YBaCuO nanoscale weak-link-based magnetometer consisting of a superconducting quantum interference device (SQUID) galvanically coupled to a 3.5 × 3.5 mm pick-up loop, reaching white flux noise levels and magnetic noise levels as low as [Formula: see text] and 100 fT/[Formula: see text] at T = 77 K, respectively. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04991DOI Listing
February 2019

Ultrahighly Saturated Structural Colors Enhanced by Multipolar-Modulated Metasurfaces.

Nano Lett 2019 Feb 13. Epub 2019 Feb 13.

The collaborative Innovation Center of Extreme Optics , Shanxi University , Taiyuan , Shanxi 030006 , China.

Colors with high saturation are of prime significance for display and imaging devices. So far, structural colors arising from all-dielectric metasurfaces, particularly amorphous silicon and titanium oxide, have exceeded the gamut of standard RGB (sRGB) space. However, the excitation of higher-order modes for dielectric materials hinders the further increase of saturation. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04923DOI Listing
February 2019

Fast Diffusion and Segregation along Threading Dislocations in Semiconductor Heterostructures.

Nano Lett 2019 Feb 14. Epub 2019 Feb 14.

Materials Department , University of California , Santa Barbara , California 93106 , United States.

Heterogeneous integration of semiconductors combines the functionality of different materials, enabling technologies such as III-V lasers and solar cells on silicon and GaN LEDs on sapphire. However, threading dislocations generated during the epitaxy of these dissimilar materials remain a key obstacle to the success of this approach due to reduced device efficiencies and reliability. Strategies to alleviate this and understand charge carrier recombination at threading dislocations now need an accurate description of the structure of threading dislocations in semiconductor heterostructures. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b03734DOI Listing
February 2019

Ultrasonic Nebulization for TEM Sample Preparation on Single-Layer Graphene Grids.

Nano Lett 2019 Feb 12. Epub 2019 Feb 12.

Department of Chemistry , University of Illinois at Urbana-Champaign , 600 S. Mathews Avenue , Urbana , Illinois 61801 , United States.

Spray-coating using ultrasonic nebulization is reported for depositing nanoparticles on a TEM grid without many of the drying artifacts that are often associated with drop-casting. Spray-coating is suitable for preparing TEM samples on fragile support materials, such as suspended single-layer graphene, that rupture when samples are prepared by drop-casting. Additionally, because ultrasonic nebulization produces uniform droplets, nanoparticles deposited by spray-coating occur on the TEM grid in clusters, whose size is dependent on the concentration of the nanoparticle dispersion, which may allow the concentration of nanoparticle dispersions to be estimated using TEM. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05117DOI Listing
February 2019

Large Scale Self-Catalyzed Sponge-Like Silicon Nanonetwork-based 3D-Anodes for High-Capacity Lithium Ion Batteries.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

Here, we report on the large scale one-step preparation, characterization and application of three-dimensional sponge-like silicon alloy composite anodes, based on the catalyst-free growth of porous silicon nano-networks directly onto highly conductive and flexible open-structure stainless steel current collectors. By the use of a key hydrofluoric acid-based chemical pre-treatment process, the originally non-catalytic stainless steel matrix becomes nano-porous and highly self-catalytic, thus greatly promoting the formation of a silicon sponge-like network at unexpectedly low growth temperatures, 380-460oC. Modulation of this unique chemical pre-treatment allows control over the morphology and loading properties of the resulting silicon network. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05127DOI Listing
February 2019

Zn-Alloyed CsPbI Nanocrystals for Highly Efficient Perovskite Light-Emitting Devices.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

Department of Materials Science and Engineering, and Centre for Functional Photonics (CFP) , City University of Hong Kong , Kowloon , Hong Kong SAR.

We alloyed Zn into CsPbI perovskite nanocrystals by partial substitution of Pb with Zn, which does not change their crystalline phase. The resulting alloyed CsPbZnI nanocrystals exhibited an improved, close-to-unity photoluminescence quantum yield of 98.5% due to the increased radiative decay rate and the decreased non-radiative decay rate. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04339DOI Listing
February 2019
1 Read
13.592 Impact Factor

Living Supramolecular Polymerization of Rod-Coil Block Copolymers: Kinetics, Origin of Uniformity, and Its Implication.

Nano Lett 2019 Feb 13. Epub 2019 Feb 13.

Shanghai Key Laboratory of Advanced Polymeric Materials, Key Laboratory for Ultrafine Materials of Ministry of Education, State Key Laboratory of Bioreactor Engineering, School of Materials Science and Engineering , East China University of Science and Technology , Shanghai 200237 , China.

We conduct Brownian dynamics simulations to explore the kinetics of living supramolecular polymerization using seeded growth of rod-coil block copolymers as a model system. We model the kinetics of supramolecular polymerization by developing kinetic theory for classical living covalent polymerization with length-dependent rate coefficients. The rate coefficient in the proposed kinetics theory decreases with increasing cylindrical micelle length, which is attributed to micelle rigidity and unique diffusion behavior. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.9b00163
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http://dx.doi.org/10.1021/acs.nanolett.9b00163DOI Listing
February 2019
1 Read

MoS2 Liquid Cell Electron Microscopy Through Clean and Fast Polymer-Free MoS2 Transfer.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

Two dimensional (2D) materials have found various applications because of their unique physical properties. For example, graphene has been used as the electron transparent membrane for liquid cell transmission electron microscopy (TEM) due to its high mechanical strength and flexibility, single-atom thickness, chemical inertness, etc. Here, we report using 2D MoS2 as a functional substrate as well as the membrane window for liquid cell TEM, which is enabled by our facile and polymer-free MoS2 transfer process. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.8b04821
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http://dx.doi.org/10.1021/acs.nanolett.8b04821DOI Listing
February 2019
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Anisotropic Ligand Nanogeometry Modulates the Adhesion and Polarization State of Macrophages.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

Department of Biomedical Engineering , The Chinese University of Hong Kong , Hong Kong , China.

Material implants trigger host reactions generated by cells, such as macrophages, which display dynamic adhesion and polarization including M1 inflammatory state and M2 anti-inflammatory state. Creating materials that enable diverse nanoscale display of integrin-binding groups, such as RGD ligand, can unravel nanoscale recruitment and ligation of integrin, which modulate cellular adhesion and activation. Here, we synthesized gold nanorods (GNRs) with various nanoscale anisotropies (i. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05150DOI Listing
February 2019
13.592 Impact Factor

Restoring Superconductivity in the Quantum Metal Phase of NbSe Using Dissipative Coupling.

Nano Lett 2019 Feb 14. Epub 2019 Feb 14.

Department of Physics , Indian Institute of Science , Bengaluru 560012 , India.

Localization arguments forbid the appearance of a metallic ground state in two dimensions. Yet, a large variety of disordered superconductors are known to manifest an anomalous metal phase in the zero temperature limit. While previous observations were confined to noncrystalline "dirty" superconductors, the recent observation of the so-called Bose metal phase in crystalline thin flakes of NbSe has sparked off intense debate. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04538DOI Listing
February 2019

Unique Nanomechanical Properties of Diamond-Lonsdaleite Biphases: Combined Experimental and Theoretical Consideration of Popigai Impact Diamonds.

Nano Lett 2019 Feb 14. Epub 2019 Feb 14.

BAM Federal Institute of Materials Research and Testing , Richard-Willstätter Str. 11 , Berlin D-12489 , Germany.

For the first time, lonsdaleite-rich impact diamonds from one of the largest Popigai impact crater (Northern Siberia) with a high concentration of structural defects are investigated under hydrostatic compression up to 25 GPa. It is found that, depending on the nature of a sample, the bulk modulus for lonsdaleite experimentally obtained by X-ray diffraction in diamond-anvil cells is systematically lower and equal to 93.3-100. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04421DOI Listing
February 2019
2 Reads

Dimensional Crossover in the Carrier Mobility of Two-Dimensional Semiconductors: The Case of InSe.

Nano Lett 2019 Feb 12. Epub 2019 Feb 12.

Department of Materials , University of Oxford , Parks Road , Oxford , OX1 3PH , United Kingdom.

Two-dimensional (2D) semiconductors are at the center of an intense research effort aimed at developing the next generation of flexible, transparent, and energy-efficient electronics. In these applications, the carrier mobility, that is the ability of electrons and holes to move rapidly in response to an external voltage, is a critical design parameter. Here, we show that the interlayer coupling between electronic wave functions in 2D semiconductors can be used to drastically alter carrier mobility and dynamics. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04799DOI Listing
February 2019

Pulsed Microwave-Pumped Drug-Free Thermoacoustic Therapy by Highly Biocompatible and Safe Metabolic Polyarginine Probes.

Nano Lett 2019 Feb 13. Epub 2019 Feb 13.

Serious side effects are plaguing traditional chemotherapy, and the development of drug-free treatment is expected to ease the dilemma. Herein, drug-free polyarginine probes are fabricated from the co-polymerization of arginine monomer and slight amount of rhodamine B monomer, which are efficient for thermoacoustic imaging and therapy with high biocompatibility and safe metabolism. Polyarginine can be strongly pumped upon pulsed microwave irradiation, generating significant thermoacoustic shockwaves, namely thermocavitation, which can in situ destroy mitochondria to initiate programmed cancer cell apoptosis. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04723DOI Listing
February 2019

Blood Circulation-Prolonging Peptides for Engineered Nanoparticles Identified via Phage Display.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

Analytical and Testing Center , South China University of Technology , Guangzhou , 510640 , P.R. China.

Sustaining blood retention for theranostic nanoparticles is a big challenge. Various approaches have been attempted and have demonstrated some success but limitations remain. We hypothesized that peptides capable of increasing blood residence time for M13 bacteriophage, a rod-shaped nanoparticle self-assembled from proteins and nucleic acids, should also prolong blood circulation for engineered nanoparticles. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04007DOI Listing
February 2019

Rayleigh-Instability-Induced Bismuth Nanorod@Nitrogen-Doped Carbon Nanotubes as A Long Cycling and High Rate Anode for Sodium-Ion Batteries.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

Materials Science and Engineering Program and Department of Mechanical Engineering , The University of Texas at Austin , Austin , Texas 78712 , United States.

Sodium-ion battery (SIB) as one of the most promising large-scale energy storage devices has drawn great attention in recent years. However, the development of SIBs is limited by the lacking of proper anodes with long cycling lifespans and large reversible capacities. Here we present rational synthesis of Rayleigh-instability-induced bismuth nanorods encapsulated in N-doped carbon nanotubes (Bi@N-C) using BiS nanobelts as the template for high-performance SIB. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b05189DOI Listing
February 2019
2 Reads

Surface Chemistry Enhancements for the Tunable Super-Liquid Repellency of Low-Surface-Tension Liquids.

Authors:
William S Y Wong

Nano Lett 2019 Feb 12. Epub 2019 Feb 12.

Nanotechnology Research Laboratory, Research School of Engineering , The Australian National University , Canberra ACT 2601 , Australia.

Super-hydrophobic, super-oleo(amphi)phobic, and super-omniphobic materials are universally important in the fields of science and engineering. Despite rapid advancements, gaps of understanding still exist between each distinctive wetting state. The transition of super-hydrophobicity to super-(oleo-, amphi-, and omni-)phobicity typically requires the use of re-entrant features. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04972DOI Listing
February 2019

Anomalously Large Spectral Shifts near the Quantum Tunnelling Limit in Plasmonic Rulers with Subatomic Resolution.

Nano Lett 2019 Feb 19. Epub 2019 Feb 19.

NanoPhotonics Centre, Cavendish Laboratory, Department of Physics , University of Cambridge , JJ Thomson Avenue , Cambridge , CB3 0HE , United Kingdom.

The resonance wavelength of a coupled plasmonic system is extremely sensitive to the distance between its metallic surfaces, resulting in "plasmon rulers". We explore this behavior in the subnanometer regime using self-assembled monolayers of bis-phthalocyanine molecules in a nanoparticle-on-mirror (NPoM) construct. These allow unprecedented subangstrom control over spacer thickness via choice of metal center, in a gap-size regime at the quantum-mechanical limit of plasmonic enhancement. Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00199DOI Listing
February 2019

Quasi-thresholdless Photon Upconversion in Metal-Organic Framework Nanocrystals.

Nano Lett 2019 Feb 12. Epub 2019 Feb 12.

Dipartimento di Scienza dei Materiali , Università degli Studi Milano-Bicocca , via R. Cozzi 53 , 20125 Milano , Italy.

Photon upconversion based on sensitized triplet-triplet annihilation ( sTTA) is considered as a promising strategy for the development of light-managing materials aimed to enhance the performance of solar devices by recovering unused low-energy photons. Here, we demonstrate that, thanks to the fast diffusion of excitons, the creation of triplet pairs in metal-organic framework nanocrystals ( nMOFs) with size smaller than the exciton diffusion length implies a 100% TTA yield regardless of the illumination condition. This makes each nMOF a thresholdless, single-unit annihilator. Read More

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http://dx.doi.org/10.1021/acs.nanolett.9b00543DOI Listing
February 2019

Non-destructive mapping of long-range dislocation strain fields in an epitaxial complex metal oxide.

Nano Lett 2019 Feb 6. Epub 2019 Feb 6.

The misfit dislocations formed at heteroepitaxial interfaces create long-ranging strain fields in addition to the epitaxial strain. For systems with strong lattice coupling, such as ferroic oxides, this results in unpredictable and potentially debilitating functionality and device performance. In this work, we use dark-field x-ray microscopy to map the lattice distortions around misfit dislocations in an epitaxial film of bismuth ferrite (BiFeO3) - a well-known multiferroic. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b03839DOI Listing
February 2019
1 Read

Bioengineered Nanocage from HBc Protein for Combination Cancer Immunotherapy.

Nano Lett 2019 Feb 11. Epub 2019 Feb 11.

State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences , Xiamen University , Xiamen , Fujian 361102 , China.

Protein nanocages are promising multifunctional platforms for nanomedicine owing to the ability to decorate their surfaces with multiple functionalities through genetic and/or chemical modification to achieve desired properties for therapeutic and diagnostic purposes. Here, we describe a model antigen (OVA peptide) that was conjugated to the surface of a naturally occurring hepatitis B core protein nanocage (HBc NC) by genetic modification. The engineered OVA-HBc nanocages (OVA-HBc NCs), displaying high density repetitive array of epitopes in a limited space by self-assembling into symmetrical structure, not only can induce bone marrow derived dendritic cells (BMDC) maturation effectively but also can be enriched in the draining lymph nodes. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.8b04722
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http://dx.doi.org/10.1021/acs.nanolett.8b04722DOI Listing
February 2019
4 Reads

Biomimetic Micromotor Enables Active Delivery of Antigens for Oral Vaccination.

Nano Lett 2019 Feb 6. Epub 2019 Feb 6.

Department of NanoEngineering and Chemical Engineering Program , University of California San Diego , La Jolla , California 92093 , United States.

Vaccination represents one of the most effective means of preventing infectious disease. In order to maximize the utility of vaccines, highly potent formulations that are easy to administer and promote high patient compliance are desired. In the present work, a biomimetic self-propelling micromotor formulation is developed for use as an oral antivirulence vaccine. Read More

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http://pubs.acs.org/doi/10.1021/acs.nanolett.8b05051
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http://dx.doi.org/10.1021/acs.nanolett.8b05051DOI Listing
February 2019
7 Reads
13.592 Impact Factor

Bright Mid-Infrared Photoluminescence from Thin-Film Black Phosphorus.

Nano Lett 2019 Feb 20. Epub 2019 Feb 20.

Department of Electrical Engineering , Yale University , New Haven , Connecticut 06511 , United States.

Recently rediscovered layered black phosphorus (BP) provides rich opportunities for investigations of device physics and applications. The band gap of BP is widely tunable by its layer number and a vertical electric field, covering a wide electromagnetic spectral range from visible to mid-infrared. Despite much progress in BP optoelectronics, the fundamental photoluminescence (PL) properties of thin-film BP in mid-infrared have rarely been investigated. Read More

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http://dx.doi.org/10.1021/acs.nanolett.8b04041DOI Listing
February 2019