Form Follows Function: Warming White LEDs Using Metal Cluster-Loaded Zeolites as Phosphors

The recent development of light-emitting diodes (LEDs) using remote phosphors to generate white light has seen this family of devices become well-positioned to replace conventional lighting. They offer higher efficiencies compared to traditional bulbs and do not contain toxic mercury, as with fluorescent lamps. However, the color quality of the light emitted from commercial white LEDs, which is typically bluish, is not yet comparable to that of incandescent lamps. In this Perspective, we discuss the potential application of luminescent metal clusters confined inside of zeolites as remote phosphors for designing warm white LEDs. Such materials may not only improve the LEDs' light quality but also help maintain device stability and efficiency, compared to other LED phosphors. Moreover, in terms of optical properties and stability of metal-loaded zeolites, the necessary improvements and drawbacks are identified, and viable solutions through rational design protocols are outlined.