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 Eu²⁺-activated Rb₃Y(PO₄)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 Rb₃Y(PO₄)₂:xEu (x = 0.1%–15%) phosphors, with the occupation of Rb1, Rb2 and Y sites by Eu²⁺, exhibit rapid luminescence quenching with optimum external PLQY of 10% due to multi-channel energy migration. Interestingly, as the Eu concentration increases above 20%, Eu²⁺ 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 Eu²⁺-activated phosphors toward high-performance inorganic luminescent materials for full-spectrum lighting.

高效无机荧光粉是发光二极管光源的理想选择，而提高活化剂的掺杂浓度是提高光致发光量子产率（PLQY）的常用方法。然而，浓度猝灭的限制对提高PLQY提出了巨大的挑战。在此，我们提出了一种基本设计原理，通过在Eu ²⁺激活的Rb ₃ Y(PO ₄ ) ₂荧光粉中分离激活剂并延长它们的距离来抑制浓度猝灭，其中不同的猝灭速率由不同晶体位点的Eu分布控制。发射蓝紫光的Rb ₃ Y(PO ₄ ) ₂ : x Eu ( x = 0.1%–15%)荧光粉，由于Eu ²⁺占据Rb1、Rb2和Y位点，在最佳外部条件下表现出快速发光猝灭。由于多通道能量迁移，PLQY 为 10%。有趣的是，当Eu浓度增加到20%以上时，Eu ²⁺更倾向于占据具有分离的多面体和大离子间距离的Rb1和Y位点，导致绿光发射并抑制浓度猝灭，实现了41%的改进的外部PLQY。我们的研究为提高Eu ²⁺激活磷光体的效率向全光谱照明的高性能无机发光材料提供了独特的设计视角。