[Daumic (OP)]

In the article "Microbiological disinfection of water and air by photocatalysis" (1), Chantal Guillard and colleagues describe the antiseptic activity of clothes impregnated with TiO2 particles. These clothes have notably a strong antiviral action but only under an UV irradiation.

In the article "Titanium dioxide photocatalysis" (2), Akira Fujishima and colleagues describe the photocatalytic activity of TiO2 particles. According to this paper, the photocatalytic action of TiO2 particles starts under a low UV irradiation, for example with an ordinary room light.

Despite the low UV content of the artificial light, a mask made of photocatalytic cloth can perhaps be active against Covid-19.

(1) https://www.sciencedirect.com/science/article/pii/S1631074807001683 [nofollow]
(2) http://solarwaterworks.org/about/tech/Titanium%20dioxide%20photocatalysis.pdf [nofollow]

[evan_au]

Does that mean you should apply sunscreen containing TiO₂ before going outdoors?

[Bored chemist]

If the cloth is fine enough to trap the virus then it doesn't need the photochemistry.
If it's not fine enough, then the virus won't be there long enough to be affected by that photochemistry.

Nice idea for hospital curtains + such