Abstract Novel trivalent europium (Eu3+)-activated La7Ta3W4O30:xEu3+ (x = 0.5 mol%–40 mol%) red-emitting phosphors were synthesized by means of a high-temperature solid-state reaction. The structure, morphology, photoluminescence, thermal-stability properties, lifetime, and color-rendering of the prepared phosphors are investigated in detail. The La7Ta3W4O30:Eu3+ phosphors show five emission peaks under near-ultraviolet (n-UV) at 397 nm, and these peaks are ascribed to the transitions of 5D0-7Fj (j = 0, 1, 2, 3 and 4) by Eu3+ ions. The optimal doped concentration of Eu3+ is 20 mol%, and the critical distance of the energy transfer between the Eu3+ ions is calculated to be 1.768 nm. The quenching temperature (T0.5) of La7Ta3W4O30:20 mol%Eu3+ is about 440 K. The quantum yield (QY) is measured to be 85.85%. The fabricated white-light-emitting diodes (w-LEDs) possess high color-rendering index (Ra) of 90, and high correlated color temperature (CCT) of 5810 K, respectively. The Commission Internationale de L’ Eclairage (CIE) coordinates are (0.311, 0.322). Therefore, the prepared phosphor has a promising application for w-LEDs.

中文翻译：

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用于近紫外激发 w-LED 的 Eu3+ 激活的 La7Ta3W4O30 红色荧光粉的光致发光特性和热稳定性

摘要 通过高温固相反应合成了新型三价铕 (Eu3+) 激活的 La7Ta3W4O30:xEu3+ (x = 0.5 mol%–40 mol%) 红色荧光粉。详细研究了制备的荧光粉的结构、形貌、光致发光、热稳定性、寿命和显色性。La7Ta3W4O30:Eu3+ 荧光粉在 397 nm 的近紫外 (n-UV) 下显示五个发射峰，这些峰归因于 Eu3+ 离子对 5D0-7Fj (j = 0、1、2、3 和 4) 的跃迁. Eu3+ 的最佳掺杂浓度为 20 mol%，计算出 Eu3+ 离子之间能量转移的临界距离为 1.768 nm。La7Ta3W4O30:20 mol%Eu3+ 的淬火温度 (T0.5) 约为 440 K。测得的量子产率 (QY) 为 85.85%。制造的白光发光二极管 (w-LED) 分别具有 90 的高显色指数 (Ra) 和 5810 K 的高相关色温 (CCT)。Commission Internationale de L' Eclairage (CIE) 坐标为 (0.311, 0.322)。因此，所制备的荧光粉在 w-LED 中具有广阔的应用前景。