Category Physics

Mutual rotation of two monolayers of a semiconducting material creates a variety of bilayer stacking patterns, depending on the twist angle. Fast and efficient characterization of these stacking patterns may aid exploration of potential applications in electronics and optoelectronics. Credit: Image credit: Oak Ridge National Laboratory, US Dept. of Energy

Recently a team measured vibrations between 2 layers to decipher their stacking patterns with low-frequency Raman spectroscopy. This will allow for 2D materials with optical and electronic properties that strongly depend on stacking configurations eg energy-efficient transistors and solar cells.

The atoms in each layer are arranged in hexagonal arrays...

A sample of the new fabric in reflected light. Credit: The picture is courtesy of the researchers

Scientists have synthesized the material that is perfect for protection of respiratory organs, analytical research and other practical purposes. An almost weightless fabric made of nylon nanofibers with a diameter <15 nm beats any other similar materials in terms of filtering and optical properties. The material is lightweight (10-20 mg/m2), almost invisible (95% light transmission: more than that of a window glass), showing low resistance to airflow and efficient interception of <1 micrometer fine particulate matter.

Previously, the same team showed reducing fiber diameter from 200 nanometers down to 20 decreased filter resistance to airflow by 2/3s, and this effect could no longer be explain...

The Solar Thermal Electrochemical Process (STEP) converts atmospheric carbon dioxide into carbon nanotubes that can be used in advanced batteries. Credit: Julie Turner, Vanderbilt University

s can be replaced with carbon recovered from the atmosphere. The team adapted a solar-powered process that converts carbon dioxide into carbon so that it produces carbon nanotubes that can be incorporated into both lithium-ion batteries like those used in electric vehicles and electronic devices and low-cost sodium-ion batteries under development for large-scale applications, such as the electric grid.

“This approach not only produces better batteries but it also establishes a value for carbon dioxide recovered from the atmosphere that is associated with the end-user battery cost unlike most efforts to...

The nuclear phase diagram: RHIC sits in the energy “sweet spot” for exploring the transition between ordinary matter made of hadrons and the early universe matter known as quark-gluon plasma. Credit: Image courtesy of Brookhaven National Laboratory

An in-depth look at the origins of matter and the environmental conditions that helped shape the universe today. Our understanding is shaped by re-creating events that constituted the Big Bang and by studying the primordial soup of fundamental particles of the very early universe. One of the best science tools for this is the Relativistic Heavy Ion Collider (RHIC), a DOE Office of Science User Facility at Brookhaven National Laboratory.

RHIC, a particle collider, is the first machine capable of mashing together heavy ions, which are atoms that h...