News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

Researchers from North Carolina State University have created 3D-printable gels with improved and highly controlled properties by merging micro- and nano-sized networks of the same materials harnessed from seaweed. The gels are composed of both a primary gel matrix and a reinforcement network that consists of micron-scale fibers, which branch multiple times into ever thinner fibers, the thinnest of which are 10 nanometers in diameter. These gels could be used to create biological scaffolds for growing cells and to develop soft robotics.  

Scientists from The University of New Mexico, the U.S. Department of Energy’s Los Alamos National Laboratory, and the Institute of Optics in Spain have published a study that gives new insight into the way collections of nanoparticles radiatively exchange heat with one another and their environment. The team found that when an arrangement of nanoparticles has some amount of heat initially stored in it, the system will approach the temperature of its environment in the same way, regardless of which particles are hot. The scientists also found that as a nanoparticle thermalizes to its environment, the nanoparticle cools down and heats back up several times, even though the environment remains at the same temperature.

Engineers at the University of California, Riverside. have developed a method to deliver nanomaterials with reliable mechanical and electric properties, which requires consistent, predictable shapes and surfaces, as well as scalable production techniques. The method involves vaporizing metals within a magnetic field to direct the reassembly of metal atoms into predictable shapes.

A team of researchers led by Cornell University has used X-ray nanoimaging to gain an unprecedented view into solid-state electrolytes, revealing previously undetected crystal defects and dislocations that may now be leveraged to create superior energy storage materials.

A multi-institutional team of researchers from the Georgia Institute of Technology and Emory University has figured out a way to deliver potent medicine to brain tumors by getting through the blood-brain barrier. The researchers packaged RNA-based drugs in robust nanocarriers, typically 100 nm in size, and deployed a modified version of ultrasound, which uses microbubbles – tiny gas pockets in the bloodstream – that vibrate in response to ultrasound waves. Focusing multiple beams of ultrasound energy onto a cancerous spot caused the microbubbles' vibrations to stretch the endothelial tissue that makes up the blood-brain barrier, creating an opening for the drugs to get through.

A patent-pending technology developed by researchers from the U.S. Department of Energy's Pacific Northwest National Laboratory has been licensed by a start-up business that is piloting the technology in several U.S. and international locations. The technology uses magnetic nanoparticles to capture valuable materials from brines. The nanoparticles consist of a form of iron oxide known as magnetite, which is used to anchor the adsorbent shell that selectively binds the compounds of interest. When exposed to a magnet, the nanoparticle's iron core migrates toward the magnet, along with the critical material to which they are bound, and the nanoparticles can be filtered from the brine.

Transitioning from fossil fuels to a clean hydrogen economy will require cheaper and more efficient ways to use renewable sources of electricity to break water into hydrogen and oxygen. But a key step in that process, known as the oxygen evolution reaction, has proven to be a bottleneck. Now, an international team led by scientists at Stanford University, the U.S. Department of Energy's SLAC National Accelerator Laboratory, the U.S. Department of Energy's Lawrence Berkeley National Laboratory, and the University of Warwick in the United Kingdom has developed a suite of advanced tools to break through this bottleneck. The scientists were able to zoom in on individual catalyst nanoparticles and watch them accelerate the generation of oxygen inside custom-made electrochemical cells. 

Researchers at MIT and colleagues have turned magic-angle twisted bilayer graphene, which is composed of atomically thin layers of carbon, into three useful electronic devices. Normally, such devices, all key to the quantum electronics industry, are created using a variety of materials that require multiple fabrication steps. The MIT approach automatically solves a variety of problems associated with those more complicated processes. As a result, the work could usher in a new generation of quantum electronic devices for applications including quantum computing. Further, the devices can be superconducting, or conduct electricity without resistance.

Researchers at the U.S. Department of Energy's National Renewable Energy Laboratory have combined perovskite nanocrystals with a network of single-walled carbon nanotubes to create a material combination they think might have interesting properties for photovoltaics or detectors. When they shined a laser at it, they found a surprising electrical response. Normally, after absorbing the light, an electrical current would briefly flow for a short period of time. But in this case, the current continued to flow and did not stop for several minutes. Such behavior is referred to as "persistent photoconductivity" and is a form of "optical memory," where the light energy hitting a device can be stored in "memory" as an electrical current. 

Modern medicine relies on an extensive arsenal of drugs to combat deadly diseases. But getting those drugs into disease-ridden cells has remained a major challenge. To tackle this difficulty, scientists from the University of California Merced, the U.S. Department of Energy’s Lawrence Livermore National Laboratory, and collaborators from the Max Planck Institute of Biophysics in Germany have used carbon nanotubes to enable direct drug delivery from liposomes through the plasma membrane into the cell’s interior by facilitating fusion of the carrier membrane with the cell.