A series of Ca₉Gd(VO₄)₇: Dy³⁺ (x = 0.01–0.20) nanophosphor crystals emitting a cool white light were synthesized by solution combustion methodology. The X-ray diffraction patterns were analyzed and processed using Rietveld refinement. The fabricated nanophosphor was found to crystallize in a trigonal crystal lattice with space group R3c(161). The morphological behavior of the prepared nanophosphor was investigated using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The photoluminescence properties of the nanophosphor correspond to cool white emission upon near-ultraviolet (NUV) excitation at 327 nm due to ⁴F_9/2 → ⁶H_15/2 (bluish) and ⁴F_9/2 → ⁶H_13/2 (yellowish) radiative relaxations at 487 nm and 576 nm respectively. Also, there is a strong occurrence of double charge transfer from O²⁻ ions to Dy³⁺ and V⁵⁺ ions with the latter being stronger due to the high positive charge of V⁵⁺ ions. Color coordinates (x = 0.2878, y = 0.3259) are consistent with white emission. Auzel's model was implemented to examine the non-radiative relaxation (113.5 ms⁻¹), radiative lifetime (1.4856 ms), and quantum efficiency (83.13%) values. The crystalline and optical behavior of the synthesized cool white emitting nanophosphor facilitates its use in near-UV-based WLEDs and other advanced solid-state lighting.

通过溶液燃烧法合成了一系列发出冷白光的 Ca ₉ Gd(VO ₄ ) ₇ : Dy ^{3+ (x = 0.01–0.20) 纳米荧光粉晶体。}使用 Rietveld 精修分析和处理 X 射线衍射图。发现制造的纳米荧光粉在具有空间群R3c（161）的三角晶格中结晶。使用透射电子显微镜（TEM）和扫描电子显微镜（SEM）研究了制备的纳米荧光粉的形态行为。^由于4 F _9/2  →  ⁶ H ，纳米荧光粉的光致发光特性对应于 327 nm 近紫外 (NUV) 激发时的冷白光发射_15/2（蓝色）和⁴ F _9/2  →  ⁶ H _13/2（黄色）辐射弛豫分别在 487 nm 和 576 nm。^{此外，从 O 2-}离子到 Dy ³⁺和 V ⁵⁺离子的双电荷转移非常频繁，后者由于 V ⁵⁺离子的高正电荷而更强。颜色坐标（x = 0.2878，y = 0.3259）与白色发射一致。实施 Auzel 模型以检查非辐射弛豫 (113.5 ms ^-1)、辐射寿命 (1.4856 ms) 和量子效率 (83.13%) 值。合成的冷白光纳米荧光粉的晶体和光学行为有助于其在基于近紫外线的 WLED 和其他先进的固态照明中的应用。