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Researchers from Columbia University, Harvard University, the University of Virginia, the University of Rhode Island, Amherst College, and Barnard College have discovered a new form of carbon, called graphullerene, made from fullerene molecules that are assembled together in a way that is reminiscent of graphene.
Researchers at Cornell University want to revolutionize how polymer nanoparticles are manufactured by using a novel combination of artificial intelligence (AI) and production techniques. As nanoparticles are being synthesized, the researchers will incorporate liquid crystals that leave an “optical fingerprint” to be read by computer vision. The resulting data will be used to train a neural network to identify information about the polymer nanoparticles and then used for real-time, automated decision-making during the assembly process.
Researchers from Pennsylvania State University and Zhejiang University have proposed that super-lubricity – a state in which friction between two contacting surfaces nearly vanishes -- may be found in water vapor and vapor in phenol (a family of organic compounds). The researchers used a silicon oxide probe on a surface of graphene to demonstrate how this might be possible. They found that super-low friction can be increased 25 times by water vapor and 45 times by phenol vapor.
Cellulose nanocrystals—bio-based nanomaterials derived from natural resources such as plant cellulose—are valuable for their use in water treatment, packaging, tissue engineering, electronics, and antibacterial coatings. Though the materials provide a sustainable alternative to non-bio-based materials, transporting them in liquid taxes industrial infrastructures and leads to environmental impacts. Now, a team of Penn State chemical engineering researchers studied the mechanisms of drying the nanocrystals and proposed nanotechnology to make the nanocrystals highly redispersible in aqueous mediums to make them easier to store and transport.
Since 2014, 37 budding engineers and technicians in the semiconductor industry have completed an internship program at the National Institute of Standards and Technology’s NanoFab facility, which provides researchers with rapid access to state-of-the-art nanoscale measurement and fabrication tools and methods, along with technical expertise. This article describes the experiences of four of these interns.
A new kind of solar panel, developed at the University of Michigan, has achieved 9% efficiency in converting water into hydrogen and oxygen – mimicking a crucial step in natural photosynthesis. Outdoors, it represents a major leap in the technology, nearly 10 times more efficient than solar water-splitting experiments of its kind. The outstanding result comes from two advances: the ability to concentrate the sunlight without destroying the semiconductor that harnesses the light, and the use of a semiconductor catalyst -- made of indium gallium nitride nanostructures, grown onto a silicon surface – that improves itself with use.
Researchers from Duke University and Arizona State University have created tiny nanoscale structures shaped like vases, bowls, and hollow spheres by using threadlike molecules of DNA. These creations demonstrate the possibilities of a new open-source software program developed by the researchers that lets users take drawings or digital models of rounded shapes and turn them into 3D structures made of DNA. The software could also allow researchers to create tiny containers to deliver drugs, as well as molds for casting metal nanoparticles with specific shapes for solar cells and medical imaging.
Researchers from the U.S. Department of Energy’s Berkeley Lab and SLAC National Accelerator Laboratory; the University of California, Berkeley; Stanford University; and the National Institute for Materials Science in Tsukuba, Japan have discovered that electrons play a surprising role in how energy is transferred between layers of two-dimensional semiconductor materials (tungsten diselenide and tungsten disulfide). Although the layers aren't tightly bonded to one another, electrons provide a bridge between them that facilitates rapid heat transfer.
To create hybrid nanomaterials, chemists marry nanocrystals of light-capturing semiconductors with "charge acceptor" molecules that act as ligands, attaching to the semiconductor's surface and transporting electrons away from the nanocrystals. A few published experiments have shown that electron transfer rates initially increase with ligand surface concentration and then fall if surface concentrations continue to rise. Now, chemists from Rice University and the University of Texas at Austin have confirmed that this is the case when the ligand molecule is an often-studied dye called perylene diimide.
Many thin films are made by using a technique called epitaxy, which consists of placing atoms of a material on a substrate, or a template of sorts, to create a thin sheet of material, one atomic layer at a time. However, most thin films created via epitaxy are "stuck" on their host substrate, limiting their uses. Now, a University of Minnesota Twin Cities-led team of scientists and engineers has found a new way to successfully create a membrane of a particular metal oxide (strontium titanate), and their method circumvents several issues that have plagued the synthesis of freestanding metal oxide films in the past.
