https://phys.org/news/2018-10-ceramic-honeycomb-air-filters-city.html

Jean-Jacques Theron, materials director at the Corning European Technology Center, France, which won the prize for adapting the company's existing technology for use in open air, said that he was inspired by colleagues working in the company's Chinese lab.

"It is very well known that particulate pollution levels in Chinese urban areas can sometimes be pretty high," he said. "There are some places where you cannot even see 10 metres ahead of you. It seems not to be that bad in Europe, but when you start to dig into the data – especially (when you look at) fine and ultrafine particles, some of them are not even visible but they have a detrimental effect to the health."