Category Physics

Vanderbilt graduate student Anna Douglas holding one of the batteries that she has modified by adding millions of quantum dots made from iron pyrite, fool’s gold. Credit: John Russell, Vanderbilt University

If you add quantum dots – nanocrystals 10,000X smaller than the width of a human hair – to a smartphone battery it will charge in 30 seconds, but the effect only lasts for a few recharge cycles. However some Vanderbilt University researtchers have found a way to overcome this problem: Making the quantum dots out of iron pyrite ie as fool’s gold, can produce batteries that charge quickly and work for dozens of cycles.

Iron pyrite is one of the most abundant materials in the earth’s surface...

IMAGE1: HD189733: The planet HD 189733b is shown here in front of its parent star. A belt of wind around the equator of the planet travels at 5400mph from the heated day side to the night side. The day side of the planet appears blue due to scattering of light from silicate haze in the atmosphere. The night side of the planet glows a deep red due to its high temperature.
Credit: Mark A. Garlick/University of Warwick

The University of Warwick discovery is the first time that a weather system on a planet outside of Earth’s solar system has been directly measured and mapped. The wind speed recorded is 20x greater than the fastest ever known on earth, where it would be 7x the speed of sound.

Tom Louden, of the University of Warwick’s Astrophysics group, said: “This is the first ever weather map...

Charge carriers in polymeric carbon nitrides always take paths perpendicular to the sheets, as Merschjann’s group has now shown. Light creates an electron-hole pair. The opposite happens when an electron and hole meet under certain conditions (forming a singlet exciton) and emit light (fluorescence). Credit: C. Merschjann.

Polymeric carbon nitride is an organic material with interesting optoelectronic properties. As an inexpensive photocatalyst, it can be used to facilitate water splitting using sunlight. Research has now investigated for the 1st time how light creates charge carriers in this class of materials and established details about charge mobility and lifetimes...

An artist’s rendering shows the layers of a new, onion-like nanoparticle whose specially crafted layers enable it to efficiently convert invisible near-infrared light to higher energy blue and UV light. Credit: Kaiheng Wei (Davidwei_loga@foxmail.com)

A dye-coated surface is 1 of 3 specially crafted layers that help the particle emit light ideal for bioimaging, solar energy harvesting and light-based security techniques. The particle’s innovation lies in its layers: a coating of organic dye, a neodymium-containing shell, and a core that incorporates ytterbium and thulium...