Abstract In order to further improve the luminescence of NaYF4:Yb,Er, we successfully constructed pitaya-like Cs0·3WO3@NaYF4:Yb, Er particles, in which Cs0·3WO3 particles were encapsulated in NaYF4:Yb, Er particles. This structure enhanced the intensity of 407, 527, 542 and 657 nm emission peaks by 10.1, 5.9, 5.5 and 1.8 times, respectively. Through calculated, the Commission Internationale de l’Eclairage (CIE) chromaticity coordinates changed from (0.28, 0.71) to (0.25, 0.73), indicating that the emission colour was tuned from yellow to green. The construction mechanism of this structure and the mechanism of upconversion (UC) luminescence enhancement were discussed. By studying the different luminescence mechanisms of NaYF4:Yb, Er excited by 1550 and 980 nm laser, we found that the UC luminescence enhancement and colour tuning of NaYF4:Yb, Er were due to the localized surface plasmon resonance (LSPR) effect of Cs0·3WO3, which can absorb more excited photons and transfer them to the Er3+ ion 4I11/2 level. Given that the transition process of green light emission is easier than red light emission, the redundant photons are more inclined to achieve emitting green light and show UC luminescence enhancement and emission colour tuning. Overall, the as-prepared novel pitaya-like Cs0·3WO3@NaYF4:Yb, Er particles exhibit strong UC luminescence enhancement and colour tuning, thus having great application prospect in the field of luminescent displays.

中文翻译：

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一种新型火龙果类 CsxWO3@NaYF4:Yb, Er 粒子的构建同时具有颜色调谐和上转换发光增强

摘要 为了进一步提高NaYF4:Yb,Er的发光性能，我们成功构建了类火龙果的Cs0·3WO3@NaYF4:Yb,Er粒子，其中Cs0·3WO3粒子包裹在NaYF4:Yb,Er粒子中。这种结构将 407、527、542 和 657 nm 发射峰的强度分别提高了 10.1、5.9、5.5 和 1.8 倍。通过计算，Commission Internationale de l'Eclairage (CIE) 色度坐标从 (0.28, 0.71) 变为 (0.25, 0.73)，表明发射颜色由黄色调至绿色。讨论了该结构的构建机理和上转换(UC)发光增强的机理。通过研究 NaYF4:Yb、Er 在 1550 和 980 nm 激光激发下的不同发光机制，我们发现 NaYF4:Yb 的 UC 发光增强和颜色调谐，Er是由于Cs0·3WO3的局域表面等离子体共振（LSPR）效应，可以吸收更多的激发光子并将它们转移到Er3+离子4I11/2能级。鉴于绿光发射的转变过程比红光发射更容易，冗余光子更倾向于实现发射绿光并表现出UC发光增强和发射颜色调谐。总体而言，所制备的新型类火龙果Cs0·3WO3@NaYF4:Yb、Er粒子具有较强的UC发光增强和颜色调节能力，在发光显示领域具有广阔的应用前景。鉴于绿光发射的转变过程比红光发射更容易，冗余光子更倾向于实现发射绿光并表现出UC发光增强和发射颜色调谐。总体而言，所制备的新型火龙果类Cs0·3WO3@NaYF4:Yb、Er粒子具有较强的UC发光增强和颜色调节能力，在发光显示领域具有广阔的应用前景。鉴于绿光发射的转变过程比红光发射更容易，冗余光子更倾向于实现发射绿光并表现出UC发光增强和发射颜色调谐。总体而言，所制备的新型类火龙果Cs0·3WO3@NaYF4:Yb、Er粒子具有较强的UC发光增强和颜色调节能力，在发光显示领域具有广阔的应用前景。