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No, not that.
After two years of COVID, the world likely is wading in close to a trillion used, disposable paper and plastic masks, by some estimates.
For those not blowing down the street, drifting into our oceans, or swelling our landfills, Russia’s National University of Science and Technology has found that they can be turned into pretty decent batteries.
After using ultrasound to disinfect the masks, the engineers dipped them into a graphene-based ink. Next, they compacted the masks and heated them to 140 °C, or 284 °F, and turned them into current-conducting pellets that work just like the electrodes of a battery.
These novel electrodes are then separated by a layer of insulation, also made from used masks, and the whole package is soaked in an electrolyte. Finally, the cell is covered by a plastic shell that, appropriately enough, is made from plastic salvaged from drug makers’ blister packs.
The result: the batteries showed an energy density of 99.7 watt-hours, nearing the threshold of their lithium-ion counterparts, which normally yield 100 to 265 watt-hours.
Even better, when the batteries were dosed with calcium-cobalt nanoparticles, their power more than doubled to 208 watt-hours.
The cells also held 82 percent of their capacity after 1,500 cycles and could deliver power for up to 10 hours.
If that’s too much trouble to take with used masks, the University of Australia is pulverizing them and including the powder in its recycled road-paving material, made primarily of ground-up concrete rubble.
TRENDPOST: These are creative and useful ways to turn waste to a useful purpose, but who will collect all those billions of masks and how? There are miles to go between a proof of concept and a practical application.
Maybe a system will be in place to repurpose the masks when the next unchecked virus arrives.
Meanwhile, Russia’s example is a good reminder that trash from one process is raw material for another.