Category Physics

A simple liquid-based battery containing a methylene blue solution (left side), and a colorless solution of leuco methylene blue (right), which is methylene blue with added electrons.
Credit: Meredith Forrest Kulwicki/University at Buffalo

Methylene blue is a common ingredient in wastewater from textile mills. But scientists think it may be possible to give this industrial pollutant a second life. In a study, they show that the dye, dissolved in water, is good at storing and releasing energy on cue. This makes the compound a promising material for redox flow batteries, which could store energy for wind farms and solar homes.

“Methylene blue is a widely used dye...

A new material developed by University of Colorado Boulder engineers can transform into complex, pre-programmed shapes via light and temperature stimuli, allowing a literal square peg to morph and fit into a round hole before fully reverting to its original form.
Credit: Bowman Lab / University of Colorado Boulder

A new material developed by University of Colorado Boulder engineers can transform into complex, pre-programmed shapes via light and temperature stimuli, allowing a literal square peg to morph and fit into a round hole before fully reverting to its original form. The controllable shape-shifting material, described today in the journal Science Advances, could have broad applications for manufacturing, robotics, biomedical devices and artificial muscles.

“The ability to form materia...

Lithium.
Credit: © vchalup / Fotolia

Chemists from the University of Waterloo have successfully resolved two of the most challenging issues surrounding lithium-oxygen batteries, and in the process created a working battery with near 100% coulombic efficiency. The new work, which appears this week in Science, proves that four-electron conversion for lithium-oxygen electrochemistry is highly reversible. The team is the first to achieve four-electron conversion, which doubles the electron storage of lithium-oxygen, also known as lithium-air, batteries.

“There are limitations based on thermodynamics,” said Linda Nazar, Canada Research Chair of Solid State Energy Materials and senior author on the project...

This cross-sectional transmission electron microscope image shows a sample used for the charge-to-spin conversion experiment. The nano-sized grains of less than 6 nanometers in the sputtered topological insulator layer created new physical properties for the material that changed the behavior of the electrons in the material.
Credit: Wang Group, University of Minnesota

Discovery could have major impact on semiconductor industry...