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

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.