Category Chemistry/Nanotechnology

An illustration of a nitrogen-doped graphene quantum dot like those being tested at Rice University for use as catalysts to reduce carbon dioxide, a greenhouse gas, into valuable hydrocarbons. Courtesy of the Ajayan Group

Graphene quantum dots may offer a simple way to recycle waste CO2 into valuable fuel rather than release it into the atmosphere or bury it underground, according to Rice University scientists. Nitrogen-doped graphene quantum dots (NGQDs) are an efficient electrocatalyst to make complex hydrocarbons from carbon dioxide, according to the research team led by Rice materials scientist Pulickel Ajayan. Using electrocatalysis, his lab has demonstrated the conversion of the greenhouse gas into small batches of ethylene and ethanol.

NGQDs worked nearly as efficiently as copper, w...

Schematic diagram of the oxygen reduction reaction (reduction of O2 into H2O) on the Pt(110) surface of the PtPb/Pt nanoplates, with purple representing Pt atoms and orange representing Pb atoms. Credit: Brookhaven National Laboratory

New platinum-based catalysts with tensile surface strain could improve fuel cell efficiency. Fuel cells are a promising technology for clean and efficient electrical power generation, but their cost, activity, and durability are key challenges to commercialization. Today’s fuel cells use expensive platinum (Pt)-based nanoparticles as catalysts to accelerate the reactions involved in converting the chemical energy from renewable fuels -such as hydrogen, methanol, and ethanol – into electrical energy...

Evan Reed, assistant professor of Materials Science & Engineering at Stanford, and graduate student Austin Sendek are using artificial intelligence to develop safer batteries. Credit: L.A. Cicero/Stanford News Service

Scientists have spent decades searching for a safe alternative to the flammable liquid electrolytes used in lithium-ion batteries. Stanford University researchers have identified nearly 2-dozen solid electrolytes that could someday replace the volatile liquids used in smartphones, laptops and other electronic devices. The results, based on techniques adapted from artificial intelligence (AI) and machine learning, are published in the journal Energy & Environmental Science.

“Electrolytes shuttle lithium ions back and forth between the battery’s positive and negative electrodes...

Cross-sectional schematic view showing the detailed structural characteristics of a SGC hybrid particle. Credit: UNIST

A new approach developed by a team of researchers, led by Prof. Jaephil Cho (School of Energy and Chemical Engineering) could hold the key to greatly improving the performance of commercial lithium-ion batteries. Prof. Cho and his research team have developed a new type anode material that would be used in place of a conventional graphite anode, which they claim will lead to lighter and longer-lasting batteries for everything from personal devices to electric vehicles.

In the study, the research team has demonstrated the feasibility of a next-generation hybrid anode using silicon-nanolayer-embedded graphite/carbon...