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

Researchers at Tufts University have created light-activated composite devices that can execute precise, visible movements and form complex three-dimensional shapes without the need for wires or other actuating materials or energy sources. The design combines programmable photonic crystals with an elastomeric composite that can be engineered at the macroscale and nanoscale to respond to illumination. The photonic material joins two layers: an opal-like film made of silk fibroin doped with gold nanoparticles, forming photonic crystals, and an underlying substrate of polydimethylsiloxane, a silicon-based polymer.

As NASA's Mars Perseverance Rover continues to explore the surface of Mars, researchers from Missouri University of Science and Technology and the U.S. Department of Energy’s Argonne National Laboratory have developed a new nanoscale metal carbide that could act as a "superlubricant" to reduce wear and tear on future rovers. The researchers discovered that the new nanoscale metal carbide works well to reduce friction and should perform better than conventional oil-based lubricants in extreme environments.

For the first time ever, a Northwestern University-led research team has peered inside a human cell to view a multi-subunit machine responsible for regulating gene expression. The researchers visualized the complex in high resolution using cryogenic electron microscopy, enabling them to better understand how it works. A breakthrough came when the researchers put the sample on a single layer of graphene oxide. By providing this support, the graphene sheet minimized the amount of sample needed for imaging and compared to the typical support used – amorphous carbon – graphene improved the signal-to-noise ratio for higher-resolution imaging.

Researchers at Northwestern University have, for the first time, created borophane – atomically thin boron that is stable at standard temperatures and air pressures. Borophene – a single-atom-thick sheet of boron – only exists inside an ultrahigh vacuum chamber, limiting its practical use outside the lab. By bonding borophene with atomic hydrogen, the researchers created borophane, which has the same exciting properties as borophene and is stable outside of a vacuum.

An interdisciplinary research team at Lehigh University has unraveled how functional biomaterials rely upon an interfacial protein layer to transmit signals to living cells concerning their adhesion, proliferation, and overall development. The researchers demonstrated that living cells respond to characteristics of the interfacial layer that arise as a consequence of microscale and nanoscale structures engineered into a substrate material. These tiny structures have an enormous impact upon the nature of the proteins and how they restructure themselves and electrostatically interact with the material, which, in turn, influences the manner in which cells attach to the substrate and develop over time.

Researchers at Northwestern University have, for the first time, created borophane – atomically thin boron that is stable at standard temperatures and air pressures. Borophene – a single-atom-thick sheet of boron – only exists inside an ultrahigh vacuum chamber, limiting its practical use outside the lab. By bonding borophene with atomic hydrogen, the researchers created borophane, which has the same exciting properties as borophene and is stable outside of a vacuum.

Researchers from Penn State and the University of Tokyo have created one-dimensional van der Waals heterostructures, a type of heterostructure made by layering two-dimensional materials that are one-atom thick. These heterostructures may lead to new, miniaturized electronics that are currently not possible. The team's research suggests that all 2D materials could be rolled into one-dimensional heterostructure cylinders, known as hetero-nanotubes.

Researchers from North Carolina State University have demonstrated that a slimy, yet tough, type of biofilm that certain bacteria make for protection can also be used to separate water and oil. The material may be useful for applications such as cleaning contaminated water. In the experiment, the researchers used the bacteria as factories of cellulose nanofibers. Then, they removed the bacteria and their non-cellulose residue and used the cellulose membrane to separate water from a solution containing both oil and water.

Tiny fluorescent semiconductor dots, called quantum dots, are useful in a variety of health and electronic technologies but are made of toxic, expensive metals. Nontoxic and economic carbon-based dots are easy to produce, but they emit less light. Now, researchers from the University of Illinois Urbana-Champaign and the University of Maryland, Baltimore County have found good and bad emitters among populations of carbon-based dots, also called carbon nanodots. This observation suggests that by selecting only super-emitters, carbon nanodots can be purified to replace toxic metal quantum dots in many applications.

Researchers from Vanderbilt University and the U.S. Department of Energy’s Oak Ridge National Laboratory have used a drop of rubbing alcohol, an office laminator, and creativity to develop scalable processes for manufacturing single-atom-thin graphene membranes. The membranes outperformed state-of-the-art commercial dialysis membranes, and the approach is fully compatible with roll-to-roll manufacturing.