As America’s newly-elected leaders do everything they can to roll back environmental regulations, the future is looking more and more like a smog-filled dystopia. But not all scientific progress has ground to a halt. Scientists at the National University of Singapore have created a transparent smog-filtering window screen that could make our lives a little less wheezy.
The problem with traditional air filters is that they not only block most of the air they’re supposed to be scrubbing free of pollutants, requiring powerful fans to boost airflow, they also block light. That’s fine for a building’s hidden heating and cooling systems, but useless for the windows in your home, that currently use mesh screens to really only block insects from getting in.
Using a chemical compound called phthalocyanine that is most commonly used for dyeing fabrics, the scientists at the National University of Singapore created organic molecules that are able to self-organise into nanoparticles, and eventually longer nanofibers. The solution is cheap to manufacture, and can be easily applied to existing thin meshes, and other non-woven materials, where it organises into those nanofibers as it dries.
The resulting filters are able to remove up to 90 per cent of pollutants and harmful particles measuring less than 2.5 microns in size, which can cause respiratory problems and other health complications. At the same time, the filers allow two-and-a-half times more purified air to flow through, compared to traditional filters.
But that’s just for a thin sheet of the new material treated with the solution. If you make it thicker, or layer the filters, its ability to remove harmful particles increases even further, say the researchers, who published their patent-pending invention in the aptly-named journal Small.
The other unexpected benefit of these new filters is that they can be made thin enough to allow light to pass through, which means they could be used to replace the screens in your home’s windows. So even if you live in a crowded urban centre with high levels of pollution and smog, you could still leave your windows open for a breath of fresh air.