Double Encapsulation of CsPbBr₃ Perovskite Nanocrystals with Inorganic Glasses for Robust Color Converters with Wide Color Gamut

A novel inorganic color converter for white LED with a single phosphor-in-glass (PiG) plate has been suggested. The PiG contained CsPbBr3 perovskite nanocrystals (PNCs), which are doubly encapsulated with inorganic glass matrixes to improve stability. A germanate glass embedding CsPbBr3 PNC precursors was used as a green phosphor and then mixed with a transparent silicate glass to fabricate a PiG plate. CsPbBr3 PNCs were induced to be formed during the sintering process for the PiG fabrication. PiG showed enhanced thermal and photo stability compared to a conventional perovskite nanocrystal embedded glass (PNEG). PiG added with CaAlSiN3:Eu2+ as a red phosphor achieved a white LED with a color gamut of up to 116% by controlling the mixing ratio. K2SiF6:Mn4+ was also used as a red phosphor and successfully composed a robust white LED with a wide color gamut up to 131% of the nation television standard committee defined color area (NTSC).