I read an article today that the best fabric for cloth masks that one lab tested is several alternating layers of cotton with silk or rayon. This combination creates static which traps even tiny particles. The article said the filtration was close to the equivalent of an N95 mask, but also warned that unless you can make it seal around the face then you won't get that level of protection.
I had some leftover silk from a prom dress I made for granddaughter a couple years ago. Lined my masks with that. So Pretty. It was even pink. Hubby will love that