[Image above] Credit: NIST
Flakes of graphene welded together into solid materials may be suitable for bone implants, according to a study led by Rice University scientists. The scientists used spark plasma sintering to weld flakes of graphene oxide into porous solids that compare favorably with the mechanical properties and biocompatibility of titanium, a standard bone-replacement material.
Iowa State University engineers have led development of a laser-treatment process that allows them to use printed graphene for electric circuits and electrodes—even on paper and other fragile surfaces. The technology could lead to many real-world, low-cost applications for printed graphene electronics, including sensors, fuel cells and medical devices.
Scientists at Iowa State University have developed a new formulation that helps to explain the self-assembly of atoms into nanoclusters and to advance the scientific understanding of related nanotechnologies. Their research offers a theoretical framework to explain the relationship between the distribution of “capture zones,” the regions that surround the nanoscale “islands” formed by deposition on surfaces, and the underlying nucleation or formation process.
Chemists at Friedrich-Alexander-Universiät Erlangen-Nürnberg have now succeeded in producing defect-free graphene directly from graphite for the first time. With the help of the additive benzonitrile, they have found a way of producing defect-free graphene directly from a solution.
Fish scales contain collagen fibers that possess a piezoelectric property, which means that an electric charge is generated in response to applying a mechanical stress. A team of researchers at Jadavpur University in Koltata, India, have harnessed this property to fabricate a bio-piezoelectric nanogenerator.
Fuel cells provide power without pollutants. But, as in the Goldilocks story, membranes in automobile fuel cells work at temperatures either too hot or too cold to be maximally effective. A polyphenyline membrane patented by Sandia National Laboratories, though, seems to work just about right, says Sandia chemist Cy Fujimoto.
As the batteries are being charged, finger-like lithium deposits form on the metal surface, which can hamper performance and even lead to short-circuits that damage or disable the battery. A team of researchers at MIT says it has carried out the most detailed analysis yet of exactly how these deposits form, and reports that there are two entirely different mechanisms at work.
MIT spinout FastCAP Systems is developing ultracapacitors, and ultracapacitor-based systems, that store up to 10 times the energy and achieve 10 times the power density of commercial counterparts. Most recently, the company developed a AA-battery-sized ultracapacitor with the perks of its bigger models, so the devices can be put in places where ultracapacitors couldn’t fit before.
Electronics integrated into textiles are gaining in popularity. The main problem with these systems tends to be the lack of a comfortable, equally wearable source of power. Scientists are now aiming to obtain the necessary energy from body heat. They have now introduced a flexible, wearable thermocell based on two different gel electrolytes.
A team of researchers from the Masdar Institute of Science and Technology and the Massachusetts Institute of Technology have developed a novel, low-cost solar thermal energy conversion system that can easily generate steam from sunlight. The solar conversion system can help make technologies that rely on steam more efficient and affordable.
The potential to develop “materials that compute” has taken another leap at the University of Pittsburgh, where researchers for the first time have demonstrated that the material can be designed to recognize simple patterns. This responsive, hybrid material, powered by its own chemical reactions, could one day be integrated into clothing or developed as a skin for “squishy” robots.
Scientists from the Moscow Institute of Physics and Technology have discovered that the depths of Uranus, Neptune, and their satellites may contain extraordinary compounds, such as carbonic and orthocarbonic acids.
Our intuition tells us that a sample of material compressed uniformly from all sides should reduce its dimensions. At the Institute of Physical Chemistry of the Polish Academy of Sciences a material has been discovered with exceptionally high negative compressibility and a previously unknown mechanism responsible for it.
A research team has discovered how they can change the surface properties of metals without affecting the mechanical stability of the metals or changing the metal characteristics themselves. This fundamentally new method is based on using an electrochemical etching process, in which the uppermost layer of a metal is roughened on a micrometer scale in a tightly controlled manner.
Researchers at Carnegie Mellon University found that the thermal conductivity of superatom crystals is directly related to the rotational disorder within those structures. Superatom crystals are periodic arrangements of C60 fullerenes and similarly sized inorganic molecular clusters. This is the first time that the process has been leveraged to create very different thermal conductivities in structurally identical materials.