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Finding lubricants that work at exceptionally high temperatures challenges researchers and industries alike. Recently, a Virginia Tech team may have uncovered a promising candidate by happenstance: transition metal spinel oxides formed on nickel-chromium-based superalloys.

Unlike common lubricants that break down under high heat, spinel oxide maintains lubrication up to 700 degrees Celsius (1,292 degrees Fahrenheit) — that’s nearly as hot as a metal forge. Enabling metallic materials to withstand hotter temperatures could ignite a new wave of metals manufacturing for industries like aerospace and nuclear energy, which demand innovations in equipment that can withstand extremely high heat. Sparked to find solutions to this critical need, the researchers were funded by multiple grants from the U.S. National Science Foundation and published their results in Nature Communications.

Spinels and spinel structured oxide belong to a group of semi-precious gemstones sometimes found alongside rubies in rare rocks. The researchers found that the mineral also holds a rare quality: the ability to self-lubricate under heat stress and friction. But there’s a catch. It only appears to do so under certain circumstances, and only when paired with a certain superalloy thus far.

Demand for metal parts that resist rigorous wear at extremely high temperatures is rising in many industries. Solid lubricants such as thin layers of molybdenum disulfide and graphite on metal surfaces can forestall this wear in some examples.

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Researchers have developed a safer and more sustainable method for extracting cobalt and nickel from junk materials. Both elements are critical components in the lithium-ion batteries that power many technologies central to modern life. More efficient extraction strategies could help reduce the impacts of future shortages while potentially mitigating water contamination and other negative environmental effects of large-scale mining operations that supply the metals.

Researchers supported by the U.S. National Science Foundation Centers for Chemical Innovation program pioneered a method to separate cobalt and nickel from ore or recycled materials using ammonia and carbonate, yielding both metals at 99% purity levels. This method provides an alternative to current methods that use harsh solvents and acids which are more energy-intensive and generate significant hazardous waste. The findings are published in the journal Chem.

As the demand for lithium-ion batteries grows through use in mobile phones, electric vehicles and even pacemakers, key components like cobalt may one day be in short supply.

“This approach offers two key benefits: increasing the capacity to produce purified cobalt from mining operations with potentially minimal environmental harm, addressing the harshness of traditional purification chemicals, and creating value for discarded batteries by providing an efficient way to separate nickel and cobalt,” says Eric Schelter, the chemist who led the research team at the University of Pennsylvania along with collaborators at Northwestern University.

“Advancements

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