[Image above] Credit: NIST
Researchers at the Universitat Politècnica de Catalunya have obtained a record efficiency of 22% by creating silicon solar cells that incorporate a surface treatment called black silicon on the front of the cell. This technique nanostructures the surface with a dry chemical attack that results in small conical tips. Incorporating black silicon reduces the loss of energy caused by the reflectance of solar cells to almost zero. This significantly increases the yield compared with traditional solar cells.
Texas Tech University researchers recently used prehistoric amber to test theories of glasses. The study tested the thermal, mechanical, and flow properties of 20 million-year-old Dominican amber glass. The researchers found that the density of the amber after 20 million years of aging is just roughly 2% more than the same amber that had been heated past its glass transition temperature and then rapidly cooled, a process referred to as thermal rejuvenation.
Nanofibers—polymer filaments only a couple of hundred nanometers in diameter—have a huge range of potential applications, from solar cells to water filtration to fuel cells. But so far, their high cost of manufacture has relegated them to just a few niche industries. MIT researchers describe a new technique for producing nanofibers that increases the rate of production fourfold while reducing energy consumption by more than 90%, holding out the prospect of cheap, efficient nanofiber production.
Take gold spirals about the size of a dime…and shrink them down about six million times. The result is the world’s smallest continuous spirals: “nano-spirals” with unique optical properties that would be almost impossible to counterfeit if they were added to identity cards, currency, and other important objects. Students and faculty at Vanderbilt University fabricated these tiny Archimedes’ spirals and characterized their optical properties.
Material scientists at ETH Zurich and the Max Planck Institute have developed a new type of carbon dioxide sensor that is smaller, has a simpler construction, and requires less energy than existing sensors. The new sensor consists of a recently developed composite material that interacts with carbon dioxide molecules and changes its conductivity depending on carbon dioxide concentration. The basis of the composite is a polymer ionic liquids.
A team of physicists from the University of Pittsburgh, the University of Wisconsin-Madison, and the U.S. Naval Research Laboratory has discovered electron pairing in strontium titanate far above the superconducting transition temperature. The phase is a long-postulated state of matter in which electrons form pairs that do not condense into a superconducting phase.