Nanophosphors have attracted much interest in applications to wide color gamut displays and micro LEDs. Since nanophosphors have a large ratio of surface area to volume, they are sensitive to surrounding environment such as oxygen and water, particularly under irradiation by excitation light. We therefore focus on photostabilities of doped nanosphosphors of YAG:Ce³⁺ [1–3], YVO₄:Bi³⁺,Eu³⁺ [4–6], and Y₂O₃: Bi³⁺,Eu³⁺ [7,8], and those of undoped nanophosphors of quantum dots of CuInS₂/ZnS [9], InP/ZnS [10], and CsPbX₃ (X = Cl, Br, I) [11]. In this talk, we mainly introduce our research on strategies to improve photostabilities of visible-emitting nanophosphors.

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