[Image above] Credit: NIST
University of Pennsylvania researchers have made an advance in manufacturing 2-D material molybdenum disulphide. By growing flakes of the material around seeds of molybdenum oxide, they have made it easier to control the size, thickness and location of the material. The team’s advance was in developing a way to control where the flakes form in the chemical vapor deposition method, by seeding the substrate with a precursor.
Measurements at BESSY II have shown how spin filters forming within magnetic sandwiches influence tunnel magnetoresistance—results that can help in designing spintronic components. Researchers have discovered that in such sandwiches combining different transition metal oxides, new interfacial effects can strongly influence the amplitude of the tunnel magnetoresistance. In doing so, the teams enhanced understanding of processes that are important for future tunnel magnetoresistance data storage devices and other spintronic components.
The materials chitin and chitosan found in crustacean shells are abundant and significantly cheaper to produce than the expensive metals such as ruthenium that are currently used in making nanostructured solar-cells. Researchers from Queen Mary, University of London used a process known as hydrothermal carbonization to create carbon quantum dots from the widely and cheaply available chemicals found in crustacean shells. They then coat standard zinc oxide nanorods with the quantum dots to make the solar cells.
Scientists have discovered that the mineral jarosite breaks down organic compounds when it is flash-heated, with implications for Mars research. Jarosite is an iron sulphate and it is one of several minerals that NASA’s Curiosity Mission is searching for, as its presence could indicate ancient habitable environments. Researchers discovered that the Curiosity instrument’s technique—which uses intense bursts of heat called flash-heating—broke down jarosite into sulphur dioxide and oxygen, with the oxygen then destroying the organic compounds, leaving no trace of it behind.
Stanford scientists have turned a material commonly used in surgical gloves into a low-cost, highly efficient air filter. It could be used to improve facemasks and window screens, and maybe even scrub the exhaust from power plants. Using electrospinning, the researchers converted liquid polyacrylonitrile into spider-web-like fibers that are just a thousandth the diameter of a human hair. The final material allows about 70 percent transparency and yet collects 99 percent of airborne pollution particles.