The NSRCs hold joint workshops to share research and user projects that are ongoing at the five centers. These exchanges of information have provided the staff at the NSRCs with the opportunity to learn about topics/thrusts in nanoscience at the other nanocenters and to develop an understanding of the different areas of expertise among the staff members. They have also facilitated discussions towards possible future areas of collaboration between the centers and provided basic information so that potential NSRC users can be directed toward the optimal center and staff to meet their research needs.
CINT - 2017 User Meeting
Santa Fe, New Mexico 24-Sep-2017 – 27-Sep-2017
Oak Ridge, TN 31-Jul-2017 – 4-Aug-2017
CNM - 2016 User Meeting
Argonne, IL 9-May-2016 – 12-May-2016
The Foundry - 2014 User Meeting
Berkeley, CA 25-Aug-2014 – 26-Aug-2014
A collaborative team of Molecular Foundry Users and staff used computation to design and predict a new metal–organic framework (MOF) able to separate dinitrogen from methane and other methane-rich gases.
“Low-tech” solution-based route to high-performance carbon nanotube thin films.
This is a rapid, facile, route to macroscale carbon nanotube thin films exhibiting a high degree of alignment. Harnessing a spontaneous self-alignment mechanism creates ideal polarizers in the terahertz frequency range.
This “low-tech” solution offers a rapid, facile route to macroscale carbon nanotube thin films exhibiting a high degree of alignment. This harnesses a spontaneous self-alignment mechanism, enabling thin film electronics, optoelectronics and ideal polarizers from THz to visible light frequencies.
The one-dimensional character of electrons, phonons and excitons in individual single-walled carbon nanotubes leads to extremely anisotropic electronic, thermal and optical properties. Despite significant efforts to develop ways to produce large-scale architectures of aligned nanotubes, macroscopic manifestations of such properties remain limited. Here, we show that large (>cm2) monodomain films of aligned single-walled carbon nanotubes can be prepared using slow vacuum filtration. The produced films are globally aligned within ±1.5¡ (a nematic order parameter of ∼1) and are highly packed, containing ~1X106 nanotubes in a cross-sectional area of 1 μm2. The method works for nanotubes synthesized by various methods, and film thickness is controllable from a few nanometres to ∼100 nm. This approach creates ideal polarizers in the terahertz frequency range. Combining this method with recently developed sorting techniques allows for highly aligned and chirality-enriched nanotube thin-film devices, with applications as efficient polarizers and thin film transistors for optoelectronic applications.
A team of scientists from CFN, Peking University, and Soochow University designed and characterized a new fuel cell catalyst — a platinum-lead core/shell structure, shaped as a nanoplate. The catalyst shape and chemical composition dramatically enhances the oxygen evolution reaction — important for fuel cell performance — while providing stability during operation.
Femtosecond laser etching is fast enough that the material vaporizes material rather than melting or burning it. Consequently, cuts made with this laser are cleaner than other nanosecond lasers that may leave ragged edges or cause material scarring. The image demonstrates this capability by etching the CINT logo onto a human hair.
This etching enables highly accurate study of microfluidic processes in a variety of materials. At Los Alamos National Lab, rock samples are etched with the femtosecond laser to create a microfluidic device specific to the rock of interest and liquids within these devices are tested under conditions of extreme heat and pressure. Accordingly, earth scientists are able to study the movement of fluids through rock similar to deep earth conditions. It would be very difficult to study these exact conditions in the natural system.
The precise cuts made by a femtosecond laser provide enhanced precision in applications such as microfluidics. Lasers with longer exposure burn the substrate and may cause scarring, but the ultrashort pulses from the femtosecond laser vaporize the unwanted material to create etching while causing very little heat transfer to the remaining material. Further, this laser is able to etch into a wider variety of materials than previous lasers and thus provides a wider range of possible applications.
The team of scientists developed and implemented a ‘physics-aware’ algorithm to correct for missing information in experimental X-ray scattering datasets. Because the algorithm relies on well-understood physics of X-ray scattering, the ‘healing’ operation provides robust and physically-rigorous results and outperforms all other conventional image interpolation methods.
Experimental X-ray scattering images always contain missing data and artifacts, which complicate further analysis, especially rapid, automated analysis. This healing operation is an essential pre-processing step for machine-learning interpretation of scientific data.
X-ray scattering is a powerful way to measure the structure of materials at the molecular- and nano-scale. Scattering images contain features, such as peaks and rings, which encode structural information. As with most scientific data, collected X-ray scattering images are inevitably ‘incomplete,’ with missing data being due to limits of the measurement, or experimental considerations. These missing data render automated data analysis of the datasets much more difficult. In this work, the team developed an image healing algorithm designed for X-ray scattering/diffraction datasets. Because the algorithm is ‘physics-aware’ (incorporating known properties of an X-ray scattering measurement), it outperforms all other image healing methods when applied to X-ray scattering data. The healed images can then be easily fed into existing data analysis pipelines. Importantly, the image healing is also a crucial pre-processing step for input to machine-learning methods — which would otherwise tend to focus on the high-intensity — but ultimately irrelevant — image defects.
A team of users from the Stony Brook University m2M EFRC developed an efficient, ‘one-pot’ synthesis strategy for composite silver-iron battery materials, capable of delivering 2.4 times the energy density of the same composite formed by conventional mixing. Intimate contact between the two material components is the reason for the boost in energy density.
New material solutions are required to meet the growing demand for energy storage. Composites can have desirable properties, but often lack efficient preparation methods. This scalable approach provides a potential solution using an environmentally abundant material (iron).
Highly stable single photon emission (SPE) from sp3 defect sites introduced to carbon nanotubes (CNT) via chemical functionalization. Wavelength tunable quantum light emission is enabled by varying CNT diameters. Room-temperature SPE achieved for first time at 1550 nm telecom band at the largest diameters.
Significance and Impact
First known material to act as a single photon emitter at telecom wavelengths and at room temperature. Critical advance for quantum light source applications in quantum information processing and metrology.
Nanoparticles of lithium metal formed on the surface of a solid state lithium ion electrolyte by an atomic force microscope. The particle size and height can be controlled by using carefully chosen voltage amplitude and sweep rates. The particles can be as small as 50 nanometers in diameter and a few nanometers high, and can potentially be used in lithium nanobatteries. A. Kumar, T.M. Arruda, A. Tselev, I.N. Ivanov, J.S. Lawton, T.A. Zawodzinski, O. Butyaev, X. Zayats, S. Jesse, and S.V. Kalinin, “Nanometer-scale mapping of irreversible electrochemical nucleation processes on solid Li-ion electrolytes.” Scientific Reports 3, 1621 (2013)
A team of scientists at the Center for Nanoscale Materials, Northwestern University and Stony Brook University has for the first time created a two-dimensional sheet of boron known as borophene. Borophene is an unusual material because it shows many metallic properties at the nanoscale even though three-dimensional, or bulk, boron is nonmetallic and semiconducting. Because borophene is both metallic and atomically thin, it holds promise for possible applications ranging from electronics to photovoltaics. While other two-dimensional materials appear smooth at the nanoscale, borophene looks like corrugated cardboard, buckling up and down depending on how the boron atoms bind to one another. The “ridges” of this cardboard-like structure result in anisotropy, where a material’s mechanical or electronic properties become directionally dependent. Experimental measurements consisted of scanning tunneling microscopy with X-ray photoelectron spectroscopy and transmission electron microscopy to both obtain a view of the surface of the material and verify its atomic-scale thickness and chemical properties.
CFN scientists have created a general theoretical model that explains the observed wide diversity of periodic structures formed through nanoparticle self-assembly. The theory applies to a broad portfolio of experimental systems, across nanometer- and micron-length scales. The core interactions dictating the ultimate structure of the assembly are between two types of mutually attractive spherical particles.
A team of CFN users and staff showed that self-assembled, conical-shaped nanotextures expel condensing water droplets with an extremely high efficiency, rendering surfaces impervious to fog and outperforming textures with different shapes and sizes.
Creating materials with anti-fogging abilities requires more than simply endowing them with water-repellency. Here, we investigate the underlying mechanism by which the superhydrophobic properties of structured solids vanish upon exposure to fog. The degradation of water-repellency is characterized by enhanced adhesion of hot water drops to the colder textured surfaces, an effect we explain using a physical model of nucleation and growth of wet patches within textures located beneath the condensing drops. Our results demonstrate the importance of both the texture’s characteristic feature size and shape on its antifogging capacity – nanometer scale textures significantly outperforming micron-scale counterparts, and conical-shaped nanotextures providing an additional ability to expel condensing water with a high efficiency compared to cylindrical textures with the same lateral dimensions.
Ionic liquids — liquid salts made by combining positively charged cations and negatively-charged anions — have potential uses as advanced battery electrolytes. When the electrolytes contact an electrode, they form a ‘double-layer’ a few nm thick, where important electrochemical reactions take place. CFN scientists have created a technique to observe in real time how ions in the double-layer reconfigure under applied voltage bias.
Ionic liquids (IL) are salts that are liquid at around room temperature. They have a notable set of chemical and electrical properties, making them attractive for use in energy storage devices as electrolytes. A very high capacitance can be achieved when the IL comes into contact with electrified surfaces, giving rise to new possibilities for electrolyte-gated devices and supercapacitors. The structure of ILs at the liquid/solid interface formed between an IL electrolyte and an electrode in such devices is a crucial factor in determining their overall efficiency. This critical interface is confined in a region of nanometers in length and it is called an electric double layer (EDL). Although much work has been done to identify the exact structure of the EDL, acquiring information from a buried interface in real time as the structure is changing in response to applied voltage bias is no trivial task. To date, the data extracted from such buried interfaces typically represent the initial state and the final state of the EDL, rather than the process occurring in-between. In the present work a new strategy to probe the intermediate state in-situ and visualize the motion of ions in real time as a function of applied voltage is devised by utilizing photoemission electron microscopy (PEEM). In addition to the observation of the evolution of the structure of IL/electrode interface, it is also possible to probe both, working and counter electrodes at the same time. This capability enables the real-time observation of correlated responses and investigation of ion transport between the two electrified electrodes.
The operation of photonics technologies such as lasers and detectors relies on confining light within structured materials such as photonic crystals and metamaterials. In this work, the team demonstrates a new class of artificial optical media called a photonic hypercrystal, which simultaneously outputs light with high efficiency and across a broad range of wavelengths.