To circumvent the large global demand of around ∼15% of the total power requirements just for electric lighting, there is an urgent need of devolving cost-effective rare earth free phosphor-converted white light emitting diodes (pc-WLEDs). Here, we report a defect-induced long and brightly emitting rare-earth free ZnGa₂O₄ (ZGaO) with PLQY ∼19%, which could also be successfully excited with ionizing X-rays and electric currents. ZGaO also displayed persistent light for more than an hour endowed by a large density of antisite defects. The defects were further engineered in ZGaO by reacting it with different percentages of Ga₂O₃/GeO₂ yielding stoichiometric Zn₃Ga₂GeO₈ (S-ZGG), gallium excess Zn₃Ga₄GeO₁₁ (Ga-ZGG) and germanium excess Zn₃Ga₂Ge₂O₁₀ (Ge-ZGG) of zinc gallo germanate samples. The defect density follows the trend Ge-ZZG > S-ZGG > ZGaO > Ga-ZGG which is directly culminated in achieving a high PLQY of ∼26% in Ge-ZGG. But a lower defect in Ga-ZGG aided in achieving the finest white light emission with correlated color temperature (CCT) of 4267 K, color rendering index (CRI) of 91, and CIE of (0.3731, 0.3862). Overall, the newly-defined structures designed in this research are providing broadband emissions covering most of the visible spectral zone and obtained from the intrinsic defects of the bulk phosphors. We have further proposed a flexible and rare pathway to engineer such defects that tuned the broadband emission from cold white to the energy efficient warm white lighting. We believe this work is an excellent contribution to resolve the issues of expensive RE doping, doping induced strain, complex organic synthesis, safety concern, and serve as a strategic pathway to design thermally stable and cost effective, on demand rare earth free tunable LED with suitable CCT and high CRI.

为了满足全球电力照明约占总电力需求 15% 左右的巨大需求，迫切需要开发具有成本效益的无稀土磷转换白光发光二极管 (pc-WLED)。在这里，我们报道了一种缺陷诱导的长而明亮的无稀土发光ZnGa ₂ O ₄ (ZGaO)，其PLQY约为19%，它也可以成功地用电离X射线和电流激发。由于高密度的反位缺陷，ZGaO 还显示出持续一个多小时的持续光。_{通过与不同百分比的 Ga 2} O ₃ /GeO ₂反应，进一步设计 ZGaO 中的缺陷，产生化学计量的 Zn ₃ Ga ₂GeO ₈ (S-ZGG)、镓过量 Zn ₃ Ga ₄ GeO ₁₁ (Ga-ZGG) 和锗过量 Zn ₃ Ga ₂ Ge ₂ O ₁₀(Ge-ZGG) 镓锗酸锌样品。缺陷密度遵循 Ge-ZZG > S-ZGG > ZGaO > Ga-ZGG 的趋势，最终在 Ge-ZGG 中实现约 26% 的高 PLQY。但 Ga-ZGG 的较低缺陷有助于实现最佳的白光发射，相关色温 (CCT) 为 4267 K，显色指数 (CRI) 为 91，CIE 为 (0.3731, 0.3862)。总体而言，本研究中设计的新定义的结构提供了覆盖大部分可见光谱区的宽带发射，并且是从块状磷光体的固有缺陷中获得的。我们进一步提出了一种灵活且罕见的途径来设计此类缺陷，将宽带发射从冷白光调整为节能的暖白光。我们相信这项工作对解决昂贵的稀土掺杂问题做出了卓越的贡献，