Inactivation of novel coronavirus and alpha variant by photo-renewable CuxO/TiO2 nanocomposites

Abstract

In order to reduce infection risk of novel coronavirus (SARS-CoV-2), we developed photocatalysts with nanoscale rutile TiO2 (4-8 nm) and CuxO (1-2 nm or less). Their extraordinarily small size leads to high dispersity and good optical transparency, besides large active surface area. Those photocatalysts can be applied to white and translucent latex paints and a transparent varnish. Although Cu2O clusters involved in the paint coating undergo gradual aerobic oxidation in the dark, the oxidized clusters are re-reduced under >380 nm light.The paint coating inactivated novel coronavirus and its alpha (B.1.1.7) variant under irradiation with fluorescent light for 3 h. The coating also exhibited antivirus effects on influenza A virus, feline calicivirus and bacteriophage Qβ. The photocatalysts would be applied to practical coatings and lower the risk of coronavirus infection via solid surfaces.