Rare-Earth Doped Upconverting Nanophosphors for Light-Mediated Biocidal Surface Development

Since the earliest civilization, diminishing the occurrence and subsequent transmission of pathogenic microorganisms in the indoor environment has been one of the utmost priorities to the human society. In line with intensive research towards the surface disinfection through the use of several photocatalytic processes, rare-earth doped upconverting nanophosphors (UCNPs) have recently drawn a great attention on the basis of their purely optical phenomenon of directly converting visible light into germicidal ultraviolet radiation (namely ultraviolet C) via the unique photoluminescence process namely ‘upconversion’. The efficient upconversion of abundant visible light into ultraviolet photons in the germicidal range and, consequently, effective biocidal action while coated onto surfaces enable UCNPs as a potential candidate to be used for inhibiting germ spreading through the inanimate surface in public places, hospitals and so forth.