Scientists have discovered a new method for creating hollow metallic nanostructures with regularly spaced and sized pores. They used advanced electron tomography to collect three-dimensional images at different stages of synthesis. The images allowed the scientists to track the transition from gold nanocubes, with sharp corners, to gold-silver alloy nanowrappers, with pores at their corners. The pores are large and regular enough to hold drug-carrying nanoparticles.
Press Releases: Research Funded by Agencies Participating in the National Nanotechnology Initiative
March 24, 2020(Funded by the U.S. Department of Energy)
March 24, 2020(Funded by the National Science Foundation and the National Geospatial-Intelligence Agency)
Graphene-based biosensors could usher in an era of liquid biopsy, detecting DNA cancer markers circulating in a patient's blood or serum. But current designs need a lot of DNA. In a new study, researchers at the University of Illinois at Urbana-Champaign have found that crumpling graphene makes it more than 10,000 times more sensitive to DNA by creating electrical "hot spots."
March 20, 2020(Funded by the U.S. Department of Energy)
Replacing precious metal catalysts with those based on more abundant metals such as iron would significantly decrease their cost. But iron catalysts, while highly efficient, tend to quickly deactivate. Creating structures with iron that are active enough to promote the reaction without becoming deactivated could open the door to using these catalysts in practical applications. Researchers at the U.S. Department of Energy’s Brookhaven National Laboratory found a structure that might be able to do just that. They prepared a thin layer of iron oxide nanoparticles on top of a gold surface and discovered that dislocation lines appearing on the iron oxide surface are very active and are not deactivated.
March 20, 2020(Funded by the National Science Foundation and the National Institute of Food and Agriculture/U.S. Department of Agriculture)
Researchers at Duke University and Michigan State University have engineered a novel type of supercapacitor that remains fully functional even when stretched to eight times its original size. It does not exhibit any wear and tear from being stretched repeatedly and loses only a few percentage points of energy performance after 10,000 cycles of charging and discharging. To make the stretchable supercapacitors, the researchers first grew a carbon nanotube forest—a patch of millions of nanotubes just 15 nanometers in diameter and 20-30 micrometers in length—on top of a silicon wafer. The researchers then coated a thin layer of gold nanofilm on top of the carbon nanotube forest.
March 19, 2020(Funded by the U.S. Department of Energy)
Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory have developed an artificial photosynthesis system, made of nanotubes, that appears capable of performing all the key steps of artificial photosynthesis. The scientists have demonstrated that their design allows for the rapid flow of protons from the interior space of the nanotube, where they are generated from splitting water molecules, to the outside, where they combine with carbon dioxide and electrons to form the fuel. Now that the team has showcased how the nanotubes can perform all the photosynthetic tasks individually, they are ready to begin testing the complete system. The individual unit of the system will be small square “solar fuel tiles” (several inches on a side) containing billions of the nanotubes sandwiched between a floor and ceiling of thin, slightly flexible silicate, with the nanotube openings piercing through these covers.
March 18, 2020(Funded by the National Science Foundation and the U.S. Army Corps of Engineers)
As flowers bloom and fruits ripen, they emit a colorless, sweet-smelling gas called ethylene. MIT chemists have now created a tiny sensor that can detect this gas in concentrations as low as 15 parts per billion, which they believe could be useful in preventing food spoilage. The sensor is made from semiconducting cylinders called carbon nanotubes.
March 12, 2020(Funded by the U.S. Department of Energy)
A team of scientists led by the U.S. Department of Energy's (DOE) Brookhaven National Laboratory and Lawrence Berkeley National Laboratory has captured in real time how lithium ions move in lithium titanate (LTO) nanoparticles, which are present in battery electrodes. The scientists discovered that distorted arrangements of lithium and surrounding atoms in LTO “intermediates” (structures of LTO with a lithium concentration between that of its initial and end states) provide an "express lane" for the transport of lithium ions.
March 12, 2020(Funded by the National Science Foundation)
It's not enough to take antibiotic-resistant bacteria out of wastewater to eliminate the risks they pose to society. The bits they leave behind have to be destroyed, as well. Researchers at Rice University's Brown School of Engineering have developed a new strategy for "trapping and zapping" antibiotic-resistant genes, the pieces of bacteria that, even though their hosts are dead, can find their way into and boost the resistance of other bacteria. The researchers used molecular-imprinted graphitic carbon nitride nanosheets to absorb and degrade these genetic remnants in sewage system wastewater before they have the chance to invade and infect other bacteria.
March 10, 2020(Funded by the Army Research Office, the National Science Foundation and the Air Force Office of Scientific Research)
Researchers at the University of Illinois at Urbana-Champaign have identified how twisted graphene sheets behave and their stability at different sizes and temperatures. The scientists performed computer simulations at different temperatures for different sizes of graphene sheets and then used insights from these simulations to develop an analytical model to predict the number of local stable states and the critical temperature required to reach each of these states.
Making More MXene: Researchers Unveil a Scalable Production System for the Promising, 2-D NanomaterialsMarch 10, 2020(Funded by the Office of the Director of National Intelligence, the Intelligence Advanced Research Projects Activity, the National Science Foundation, and the U.S. Department of Energy)
For more than a decade, two-dimensional nanomaterials, such as graphene, have been touted as the key to making better microchips, batteries, and antennas. But a significant challenge remains: ensuring that these atom-thin building materials can be produced in bulk quantities without losing their quality. For one of the most promising new types of 2D nanomaterials, MXenes, that's no longer a problem. Researchers at Drexel University and the Materials Research Center in Ukraine have designed a system that can be used to make large quantities of the material while preserving its unique properties.