Nano Letters

Publisher: American Chemical Society, American Chemical Society

Journal description

A central forum for scientists involved in nanoscale research, among a wide range of disciplines that include physical and materials chemistry, biotechnology, and applied physics. Nano Letters reports on fundamental research in all branches of the theory and practice of nanoscience and nanotechnology. It will provide rapid disclosure of the key elements of a study, publishing preliminary, experimental, and theoretical results on the physical, chemical, and biological phenomena, processes and applications of structures within the nanoscale range. Areas of interest include: Synthesis and processing of organic, inorganic, and hybrid nanosized materials by physical, chemical, and biological methods; Modeling and simulation of synthetic, assembly, and interaction processes; Characterization of unique size properties; Realization and application of novel nanostructures and nanodevices. This is the second letters journal launched by ACS, following the 1999 release of Organic Letters, and charged with the same mission: To rapidly communicate preliminary significant research results.

Current impact factor: 13.59

Impact Factor Rankings

2016 Impact Factor Available summer 2017
2014 / 2015 Impact Factor 13.592
2013 Impact Factor 12.94
2012 Impact Factor 13.025
2011 Impact Factor 13.198
2010 Impact Factor 12.186
2009 Impact Factor 9.991
2008 Impact Factor 10.371
2007 Impact Factor 9.627
2006 Impact Factor 9.96
2005 Impact Factor 9.847
2004 Impact Factor 8.449
2003 Impact Factor 6.144
2002 Impact Factor 5.033

Impact factor over time

Impact factor
Year

Additional details

5-year impact 14.89
Cited half-life 4.90
Immediacy index 2.55
Eigenfactor 0.36
Article influence 4.89
Website Nano Letters website
Other titles Nano letters (Online), Nano letters
ISSN 1530-6992
OCLC 44445939
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

American Chemical Society

  • Pre-print
    • Author cannot archive a pre-print version
  • Restrictions
    • Must obtain written permission from Editor
    • Must not violate ACS ethical Guidelines
  • Post-print
    • Author cannot archive a post-print version
  • Restrictions
    • If mandated by funding agency or employer/ institution
    • If mandated to deposit before 12 months, must obtain waiver from Institution/Funding agency or use AuthorChoice
    • 12 months embargo
  • Conditions
    • On author's personal website, pre-print servers, institutional website, institutional repositories or subject repositories
    • Non-Commercial
    • Must be accompanied by set statement (see policy)
    • Must link to publisher version
    • Publisher's version/PDF cannot be used
    • If mandated sooner than 12 months, must obtain waiver from Editors or use AuthorChoice
    • Reviewed on 07/08/2014
  • Classification
    white

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: The development of safe, stable, and long-life Li-ion batteries is being intensively pursued to enable the electrification of transportation and intelligent grid applications. Here, we report a new solid-state Li-ion battery technology, using a solid nanocomposite electrolyte composed of porous silica matrices with in situ immobilizing Li(+)-conducting ionic liquid, anode material of MCMB, and cathode material of LiCoO2, LiNi1/3Co1/3Mn1/3O2, or LiFePO4. An injection printing method is used for the electrode/electrolyte preparation. Solid nanocomposite electrolytes exhibit superior performance to the conventional organic electrolytes with regard to safety and cycle-life. They also have a transparent glassy structure with high ionic conductivity and good mechanical strength. Solid-state full cells tested with the various cathodes exhibited high specific capacities, long cycling stability, and excellent high temperature performance. This solid-state battery technology will provide new avenues for the rational engineering of advanced Li-ion batteries and other electrochemical devices.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: The magnetic properties of a nanoscale system are inextricably linked to its local environment. In ad-atoms on surfaces and inorganic layered structures the exchange interactions result from the relative lattice positions, layer thicknesses and other environmental parameters. Here, we report on a sample-dependent sign inversion of the magnetic exchange coupling between the three unpaired spins of an organic triradical molecule embedded in a three-terminal device. This ferro-to-antiferromagnetic transition is due to structural distortions and results in a high-to-low spin ground state change in a molecule traditionally considered to be a robust high-spin quartet. Moreover, the flexibility of the molecule yields an in-situ electric tunability of the exchange coupling via the gate electrode. The findings open a route to the controlled reversal of the magnetic states in organic molecule-based nanodevices by mechanical means, electrical gating or chemical tailoring.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: We study podosome formation and development in activated monocytes (THP1) at ICAM1 (intercellular adhesion molecule 1) nanopatterns of circular and ring shaped domains and show that cellular binding to a pre-clustered ICAM1 nanopattern requires ligand patches of at least 200nm (corresponding to 14 or more integrins). Podosome-like adhesion formation depends on the structure of the ligand pattern under the developing podosome with larger single domains promoting adhesion in a single patch and multiple smaller domains allowing podosome formation by integration of at least 2 smaller domains on either side of the podosome core. Maturation to rosette structures and recruitment of proteases was only observed with macroscopic ICAM1 presentation.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: We report measurements of the shot noise on single-molecule Au-1,4-benzenedithiol (BDT)-Au junctions, fabricated with the mechanically controllable break junction (MCBJ) technique at 4.2 K in a wide range of conductance values from 10(-2) to 0.24 conductance quanta. We introduce a simple measurement scheme using a current-amplifier and a spectrum analyzer, and that does not imply special requirements regarding the electrical leads. The experimental findings provide evidence that the current is carried by a single conduction channel throughout the whole conductance range. This observation suggests that the number of channels is limited by the Au-thiol bonds and that contributions due to direct tunneling from the Au to the π system of the aromatic ring are negligible also for high conductance. The results are supported by quantum transport calculations using density functional theory (DFT).
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: We describe the realization of van der Waals (vdW) heterostructures with accurate rotational alignment of individual layer crystal axes. We illustrate the approach by demonstrating a Bernal-stacked bilayer graphene formed using successive transfers of monolayer graphene flakes. The Raman spectra of this artificial bilayer graphene possess a wide 2D band which is best fit by four Lorentzians, consistent with Bernal stacking. Scanning tunneling microscopy reveals no moiré pattern on the artificial bilayer graphene, and tunneling spectroscopy as a function of gate voltage reveals a constant density of states, also in agreement with Bernal stacking. To further illustrate the applicability of this technique to realize vdW heterostructuctures in which the functionality is critically dependent on rotational alignment, we demonstrate resonant tunneling double bilayer graphene heterostructures separated by hexagonal boron-nitride dielectric.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Superconductivity in FeSe is greatly enhanced in films grown on SrTiO3 substrates, although the mechanism behind remains unclear. Recently, surface potassium (K) doping has also proven able to enhance the superconductivity of FeSe. Here by using scanning tunneling microscopy, we compare the K doping dependence of the superconductivity in FeSe films grown on two substrates: SrTiO3 (001) and graphitized SiC (0001). For thick films (20 unit cells (UC)), the optimized superconducting (SC) gaps are of similar size (~9 meV) regardless of the substrate. However, when the thickness is reduced to a few UC, the optimized SC gap is increased up to ~15meV for films on SrTiO3, while it remains unchanged for films on SiC. This clearly indicates that the FeSe/SrTiO3 interface can further enhance the superconductivity, beyond merely doping electrons. Intriguingly, we found that this interface enhancement decays exponentially as the thickness increases, with a decay length of 2.4 UC which is much shorter than the lengthscale for relaxation of the lattice strain, pointing to interfacial electron-phonon coupling as the likely origin.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: P-type transparent conducting films of nanocrystalline (CuS)x:(ZnS)1-x were synthesized by facile and low-cost chemical bath deposition. Wide angle x ray scattering (WAXS) and high resolution transmission electron microscopy (HRTEM) were used to evaluate the nanocomposite structure, which consists of sub-5-nm crystallites of sphalerite ZnS and covellite CuS. Film transparency can be controlled by tuning the size of the nanocrystallites which is achieved by adjusting the concentration of the complexing agent during growth; optimal films have optical transmission above 70% in the visible range of the spectrum. The hole conductivity increases with the fraction of the covellite phase and can be as high as 1000 S cm(-1), which is higher than most reported p-type transparent materials and approaches that of n type transparent materials such as indium tin oxide (ITO) and aluminum doped zinc oxide (AZO). Heterojunction p-(CuS)x:(ZnS)1-x/n-Si solar cells were fabricated with the nanocomposite film serving as a hole selective contact. Under 1 sun illumination, an open circuit voltage of 535 mV was observed. This value compares favorably to other emerging heterojunction Si solar cells which use a low temperature process to fabricate the contact, such as single-walled carbon nanotube/Si (370-530 mV) and graphene/Si (360-552 mV).
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Electrical transport in monolayer graphene on SrTiO3 (STO) thin film is examined in order to promote gate-voltage scaling using a high-k dielectric material. The atomically flat surface of thin STO layer epitaxially grown on Nb-doped STO single-crystal substrate offers good adhesion between the high-k film and graphene, resulting in non-hysteretic conductance as a function of gate voltage at all temperatures down to 2 K. The two-terminal conductance quantization under magnetic fields corresponding to quantum Hall states survives up to 200 K at a magnetic field of 14 T. In addition, the substantial shift of charge neutrality point in graphene seems to correlate with the temperature-dependent dielectric constant of the STO thin film, and its effective dielectric properties could be deduced from the universality of quantum phenomena in graphene. Our experimental data prove that the operating voltage reduction can be successfully realized due to the underlying high-k STO thin film, without any noticeable degradation of graphene device performance.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Emerging two-dimensional semiconductor materials possess a giant second order nonlinear response due to excitonic effects while the monolayer thickness of such active materials limits their use in practical nonlinear devices. Here, we report 3300 times optomechanical enhancement of second harmonic generation (SHG) from a MoS2 monolayer in a doubly resonant on-chip optical cavity. We achieve this by engineering the nonlinear light-matter interaction in a micro-electro-mechanical system (MEMS) enabled optical frequency doubling device based on an electrostatically tunable Fabry-Perot (FP) microresonator. Our versatile optomechanical approach will pave the way for next generation efficient on-chip tunable light sources, sensors, and systems based on molecularly thin materials.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: We report that reduced graphene-coated gold nanoparticles (r-GO-AuNPs) are excellent visible-light-responsive photocatalysts for the photoconversion of CO2 into formic acid (HCOOH). The wavelength-dependent quantum and chemical yields of HCOOH shows a significant contribution of plasmon-induced hot electrons for CO2 photoconversion. Furthermore, the presence and reduced state of the graphene layers are critical parameters for the efficient CO2 photoconversion because of the electron mobility of graphene. With an excellent selectivity toward HCOOH (>90%), the quantum yield of HCOOH using r-GO-AuNPs is 1.52%, superior to that of Pt-coated AuNPs (quantum yield: 1.14%). This indicates that r-GO is a viable alternative to platinum metal. The excellent colloidal stability and photocatalytic stability of r-GO-AuNPs enables CO2 photoconversion under more desirable reaction conditions. These results highlight the role of reduced graphene layers as highly efficient electron acceptors and transporters to facilitate the use of hot electrons for plasmonic photocatalysts. The femtosecond transient spectroscopic analysis also shows 8.7 times higher transport efficiency of hot plasmonic electrons in r-GO-AuNPs compare with AuNPs.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Thanks to their remarkably high activity towards ORR platinum-based octahedrally shaped nanoparticles have attracted ever increasing attention in last years. Although high activities for ORR catalysts have been attained, the practical use is still limited by their long-term stability. In this work, we present Rh-doped Pt-Ni octahedral nanoparticles with high activities up to 1.14 A mgPt-1 combined with improved performance and shape stability compared to previous bimetallic Pt-Ni octahedral particles. The synthesis, the electrocatalytic performance of the particles towards ORR and atomic degradation mechanisms are investigated with a major focus on a deeper understanding of strategies to stabilize morphological particle shape and consequently their performance. Rh surface doped octahedral Pt-Ni particles were prepared at various Rh levels. At and above about 3 at.% the nanoparticles maintained their octahedral shape even past 30,000 potential cycles, while undoped bimetallic reference nanoparticles show a complete loss in octahedral shape already after 8,000 cycles in the same potential window. Detailed atomic insight in these observations is obtained from aberration-corrected scanning transmission electron microscopy (STEM) and energy dispersive X-ray (EDX) analysis. Our analysis shows that it is the migration of Pt surface atoms, not - as commonly thought - the dissolution of Ni that constitutes the primary origin of the octahedral shape loss for Pt-Ni nanoparticles. Using small amounts of Rh we were able to suppress the migration rate of platinum atoms and consequently suppress the octahedral shape loss of Pt-Ni nanoparticles.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Owing to direct band gap and strong spin-orbit coupling, monolayer transition-metal dichalcogenides (TMDs) exhibit rich new physics and great applicable potentials. The remarkable valley contrast and light emission promise such two-dimensional semiconductors a bright future of valleytronics and light-emitting diodes (LEDs). Though the electroluminescence (EL) has been observed in mechanically exfoliated small flakes of TMDs, considering real applications, a strategy which could offer mass-product and high compatibility is greatly demanded. Large-area and high quality samples prepared by chemical vapour deposition (CVD) are perfect candidates towards such goal. Here, we report the first demonstration of electrically tunable chiral EL from CVD-grown monolayer WS2 by constructing a p-i-n heterojucntion. The chirality contrast of the overall EL reaches as high as 81% and can be effectively modulated by forward current. The success of fabricating valley LEDs (vLEDs) based on CVD WS2 opens up many opportunities for developing large-scale production of unconventional 2D optoelectronic devices.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Herein, a proof-of-concept of novel hybrid rechargeable battery based on electrochemical reactions of both nickel-zinc and zinc-air batteries is demonstrated using NiO/Ni(OH)2 nanoflakes self-assembled into mesoporous spheres as the active electrode material. The hybrid battery operates on two sets of fundamentally different battery reactions combined at the cell level, unlike in other hybrid systems where batteries of different reactions are simply connected through an external circuitry. As a result of combining nickel-zinc and zinc-air reactions, the hybrid battery demonstrates both remarkably high power density (volumetric: 14000 W L(-1), gravimetric: 2700 W kg(-1)) and energy density of 980 W h kg(-1), significantly outperforming the performances of a conventional zinc-air battery. Furthermore, the hybrid battery demonstrates excellent charge rate capability, up to 10 times faster than the rate of discharge, without any capacity and voltage degradations, which makes it highly suited for large-scale applications such as electric vehicle propulsion and smart-grid energy storage.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Nanoscale control of charge doping in two dimensional (2D) materials permits the realization of electronic analogs of optical phenomena, relativistic physics at low energies, and technologically promising nanoelectronics. Electrostatic gating and chemical doping are the two most common methods to achieve local control of such doping. However, these approaches suffer from complicated fabrication processes that introduce contamination, change material properties irreversibly, and lack flexible pattern control. Here we demonstrate a clean, simple, and reversible technique that permits writing, reading, and erasing of doping patterns for 2D materials at the nanometer scale. We accomplish this by employing a graphene/boron nitride (BN) heterostructure that is equipped with a bottom gate electrode. By using electron transport and scanning tunneling microscopy (STM), we demonstrate that spatial control of charge doping can be realized with the application of either light or STM tip voltage excitations in conjunction with a gate electric field. Our straightforward and novel technique provides a new path towards on-demand graphene pn junctions and ultra-thin memory devices.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: In this letter, we use first principles simulations to demonstrate the absence of Fermi-level pinning when graphene is in contact with transition metal dichalcogenides (TMDs). We find that formation of either an ohmic or Schottky contact is possible. Then we show that due to the shallow density of states around its Fermi-level, the work function of graphene can be tuned by ion adsorption. Finally we combine work function tuning of graphene and an ideal contact between graphene and TMDs to propose an ionic barristor design that can tune the work function of graphene with a much wider margin than current barristor designs, achieving a dynamic switching among p-type ohmic contact, Schottky contact, and n-type ohmic contact in one device.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: We propose to use edge-modified phosphorene nanoflakes (PNFs) as donor and accepter materials for heterojunction solar cells. By using density functional theory based calculations, we show that heterojunctions consisting of hydrogen and fluorine passivated PNFs have a number of desired optoelectronic properties that are suitable for use in a solar cell. We explain why these properties hold for this type of heterojunctions. Our calculations also predict that the maximum energy conversion efficiency of this type of heterojunctions, which can be easily fabricated, can be as high as 20%, making them extremely competitive with other types of 2D heterojunctions.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Extensive efforts to develop highly active and strongly durable electrocatalyst for oxygen reduction are motivated by a need for metal-air batteries and fuel cells. Here, we report a very promising catalyst prototype of structurally ordered Pd-based alloys, Pd3Pb intermetallic compound. Such structurally ordered Pd3Pb/C exhibits significant increase in mass activity. More importantly, ordered Pd3Pb/C is highly durable and achieves higher cell efficiency and several times longer cycle life than conventional Pt/C catalysts in Zn-air batteries. Interestingly, ordered Pd3Pb/C possesses very high methanol tolerance during electrochemical oxygen reduction, which make it an excellent methanol-tolerant cathode catalyst for alkaline polymer electrolyte membrane fuel cells. This study provides a promising route to optimize the synthesis of ordered Pd-based intermetallic catalysts for fuel cells and metal-air batteries.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Bisphenol A (BPA) aggregates on Ag(111) shows a polymorphism between two supramolecular motifs leading to formation of distinct networks depending on thermal energy. With rising temperature a dimeric pairing scheme reversibly converts into a trimeric motif, which forms a hexagonal superstructure with complex dynamic characteristics. The trimeric arrangements notably organize spontaneously into a self-assembled one-component array with supramolecular BPA rotors embedded in a two-dimensional stator sublattice. By varying the temperature, the speed of the rotors can be controlled as monitored by direct visualization. A combination of scanning tunneling microscopy and dispersion-corrected density-functional tight-binding (DFTB-vdW(surf)) based molecular modeling reveals the exact atomistic position of each molecule within the assembly as well as the driving force for the formation of the supramolecular rotors.
    No preview · Article · Feb 2016 · Nano Letters
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    ABSTRACT: Memristive devices, whose conductance depends on previous programming history are of significant interest for building non-volatile memory and brain-inspired computing systems. Here, we report half-integer quantized conductance transitions G = (n/2)(2e(2)/h) for n = 1, 2, 3, . . . in Cu/SiO2/W memristive devices observed below 300 mV at room temperature. This is attributed to the nanoscale filamentary nature of Cu conductance pathways formed inside SiO2. Retention measurements also show spontaneous filament decay with quantized conductance levels. Numerical simulations shed light into the dynamics underlying the data retention loss mechanisms and provides new insights into the nanoscale physics of memristive devices and trade-offs involved in engineering them for computational applications.
    No preview · Article · Feb 2016 · Nano Letters