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

A group of researchers led by Cornell University has identified a new way to harness the antioxidant and antibacterial properties of a botanical compound to make nanofiber-coated cotton bandages that fight infection and help wounds heal more quickly. The biofunctionalized dressing has excellent antibacterial performance against gram-negative and gram-positive bacterial species and effectively eradicated E. coli and staph bacteria in testing.

Scientists at the U.S. Department of Energy’s Los Alamos National Laboratory are developing nanometer-scale light-based systems that could deliver breakthroughs for ultrafast microelectronics and night vision capabilities. The scientists have designed and fabricated asymmetric, nano-sized gold structures on an atomically thin layer of graphene. The gold structures, called nanoantennas, capture and focus light waves, forming optical "hot spots" that excite the electrons within the graphene. The hot spots are located only at the sharp tips of the nanoantennas, leading to a pathway on which the excited hot electrons flow.  

One of the most important components of satellites that enable telecommunication is the waveguide, which is a metal tube for guiding radio waves. It is also one of the heaviest payloads satellites carry into orbit. Now, researchers from Drexel University and the University of British Columbia are trying to lighten the load by creating and testing a waveguide made from 3D-printed polymers coated with a conductive nanomaterial called MXene. "MXene materials provide one of the thinnest possible coatings … that can create a conductive surface,” said Yury Gogotsi, one of the scientists involved in this study. 

Researchers from the U.S. Department of Energy’s Oak Ridge National Laboratory have pioneered a groundbreaking approach toward understanding the behavior of an electric charge in microelectronics and nanoscale material systems. The novel approach enables visualizing charge motion at the nanometer level but at speeds thousands of times faster than conventional methods. The rapid, thorough view of processes demonstrated in the new approach was previously unattainable.

In recent years, nanoporous membranes made with graphene, polymers, and silicon have been used successfully for separating gases, desalinating water, and delivering drugs, among other uses. But creating membranes that let all the right molecules pass through while keeping the undesired ones out has proven tricky. Now, researchers at Yale University have found that more distance between pores enabled a greater permeability/selectivity performance. 

Scientists from the U.S. Department of Energy's Brookhaven National Laboratory and Pacific Northwest National Laboratory have used a combination of scanning transmission electron microscopy and computational modeling to get a closer look and deeper understanding of tantalum oxide. When this amorphous oxide layer forms on the surface of tantalum – a superconductor that shows great promise for making the "qubit" building blocks of a quantum computer – it can impede the material's ability to retain quantum information. "The key is to understand the interface between the surface oxide layer and the tantalum film, because this interface can profoundly impact qubit performance," said study co-author Yimei Zhu.

Scientists at the U.S. Department of Energy's Brookhaven National Laboratory have discovered that adding a thin layer of magnesium improves the properties of tantalum, a superconducting material that shows great promise for building qubits, the basis of quantum computers. The thin layer of magnesium keeps tantalum from oxidizing, improves its purity, and raises the temperature at which it operates as a superconductor. All three properties may increase tantalum's ability to hold onto quantum information in qubits.

Engineers at the University of California San Diego have developed an ultra-sensitive sensor made with graphene that can detect extraordinarily low concentrations of lead ions in water. The device achieves a record limit of detection of lead down to the femtomolar range, which is one million times more sensitive than previous sensing technologies. The device consists of a single layer of graphene mounted on a silicon wafer. The researchers enhanced the sensing capabilities of the graphene layer by attaching a linker molecule to its surface. 

Purdue University researchers have merged the power of advanced surfaces with thermal imaging algorithms to create a device that could open new frontiers in machine vision and autonomous systems. The device, called a Spinning MetaCam, could help classify materials and provide new possibilities for technologies in security, thermography, medical imaging, and remote sensing. The Spinning MetaCam contains metasurfaces – structured electromagnetic nanoscale surfaces crafted to behave like aqueducts for water, filtering and channeling light. Unlike traditional materials, which naturally bend, reflect, or absorb light, metasurfaces manipulate light’s intensity, spectrum, and polarization. 

A team of Rice University researchers has mapped out how flecks of two-dimensional (2D) nanomaterials move in liquid. The researchers used glowing soap to tag samples of hexagonal boron nitride nanosheets and make their motion visible. Videos of this motion allowed researchers to map out the trajectories of the samples and determine the relationship between their size and how they move. These findings could help scientists assemble macroscopic-scale materials with the same properties as their 2D counterparts.