Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources,and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield...Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources,and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield(PLQY).However,the constraint of concentration quenching poses a great challenge for improving the PLQY.Herein,we propose a fundamental design principle by separating activators and prolonging their distance in Eu^(2+)-activated Rb_(3)Y(PO_(4))_(2)phosphors to inhibit concentration quenching,in which different quenching rates are controlled by the Eu distribution at various crystallographic sites.The blue-violet-emitting Rb_(3)Y(PO_(4))2:xEu(x=0.1%–15%)phosphors,with the occupation of Rb1,Rb2 and Y sites by Eu^(2+),exhibit rapid luminescence quenching with optimum external PLQY of 10%due to multi-channel energy migration.Interestingly,as the Eu concentration increases above 20%,Eu^(2+)prefer to occupy the Rb1 and Y sites with separated polyhedra and large interionic distances,resulting in green emission with suppressed concentration quenching,achieving an improved external PLQY of 41%.Our study provides a unique design perspective for elevating the efficiency of Eu^(2+)-activated phosphors toward high-performance inorganic luminescent materials for full-spectrum lighting.展开更多
基金supported by the National Natural Science Foundations of China(52202160)Beijing Municipal Natural Science Foundation(2232041)+4 种基金National Key R&D Program of China(2023YFB3507900)China Postdoctoral Science Foundation(BX20220027,2021M700298)Beijing Postdoctoral Research Foundation(2022-ZZ-065)Chaoyang District Postdoctoral Research Foundation(2022ZZ-015)Beijing University of Technology“Urban Carbon Neutral”Science and Technology Innovation Foundation。
文摘Highly efficient inorganic phosphors are desirable for lighting-emitting diode light sources,and increasing the doping concentration of activators is a common approach for enhancing the photoluminescence quantum yield(PLQY).However,the constraint of concentration quenching poses a great challenge for improving the PLQY.Herein,we propose a fundamental design principle by separating activators and prolonging their distance in Eu^(2+)-activated Rb_(3)Y(PO_(4))_(2)phosphors to inhibit concentration quenching,in which different quenching rates are controlled by the Eu distribution at various crystallographic sites.The blue-violet-emitting Rb_(3)Y(PO_(4))2:xEu(x=0.1%–15%)phosphors,with the occupation of Rb1,Rb2 and Y sites by Eu^(2+),exhibit rapid luminescence quenching with optimum external PLQY of 10%due to multi-channel energy migration.Interestingly,as the Eu concentration increases above 20%,Eu^(2+)prefer to occupy the Rb1 and Y sites with separated polyhedra and large interionic distances,resulting in green emission with suppressed concentration quenching,achieving an improved external PLQY of 41%.Our study provides a unique design perspective for elevating the efficiency of Eu^(2+)-activated phosphors toward high-performance inorganic luminescent materials for full-spectrum lighting.
