Category Chemistry/Nanotechnology

Electron microscopy images of perovskite quantum dots embedded in the protective alumina matrix, and a photograph of the same film stable in water. Credit: © R. Buonsanti/EPFL

EPFL scientists have built a new type of inorganic nanocomposite that makes perovskite quantum dot exceptionally stable against air exposure, sunlight, heat, and water. Quantum dots are nanometer-size, semiconducting materials whose tiny size gives them unique optical properties. Much effort has been put in building quantum dots from perovskites, which already show much promise for solar panels, LEDs and laser technologies.

The new approach to stabilize the perovskite quantum dots was developed in the lab of Raffaella Buonsanti at EPFL Valais Wallis...

Pure platinum with thin fixed foils of yttrium have been used to create the new nanoalloys that are ten times as effective as pure platinum in fuel cells. Credit: Mia Halleröd Palmgren CC BY 3.0

A new type of nanocatalyst can result in the long-awaited commercial breakthrough for fuel cell cars. Research results from Chalmers University of Technology and Technical University of Denmark show that it is possible to significantly reduce the need for platinum, a precious and rare metal, by creating a nanoalloy using a new production technique. The technology is also well suited for mass production.

“A nano solution is needed to mass-produce resource-efficient catalysts for fuel cells. With our method, only 1/10 as much platinum is needed for the most demanding reactions...

1. Nanoporous nickel cathodes for lithium oxygen batteries are ultralight, shown here balanced on flower stamens.
Credit: American Chemical Society
2. Nanoengineered Ultralight and Robust All-Metal Cathode for High-Capacity, Stable Lithium–Oxygen Batteries

Lithium-oxygen systems could someday outperform today’s lithium-ion batteries because of their potential for high energy density. However, a number of important issues, such as their poor electrochemical stability must be addressed before these systems can successfully compete with current rechargeable batteries. Now, in ACS Central Sci

ence, researchers report a new type of cathode, which could make lithium-oxygen batteries a practical option.

Xin-Bo Zhang and colleagues note that most of the problems associated with lithium-oxygen batt...

A self-healing structural color hydrogel inspired by nature A set of self-healing hydrogel films with different structural colors. Credit: Yuanjin Zhao.

A team of researchers at Southeast University in China has developed a self-healing structural hydrogel with a wide variety of applications. It has been noted for several years that one area where humanoid robots are lacking is skin tone—most robots have a pasty white complexion, which is both disturbing and likely to lead to social problems once robots become mainstream. Most artificial skin is not able to heal itself, which means that robots need skin replacement if it gets damaged or accidentally colored in undesirable ways. There is also the issue of colors fading...