Near-infrared nanophosphors have attracted attention due to their wide application fields, including component analysis, bioimaging, and spectral converters of sunlight for crystalline silicon solar cells (c-Si). Yb³⁺ ions exhibit near-infrared (NIR) luminescence at around 1000 nm, which is consistent with the first biological window and the maximum responsivity range of c-Si. Therefore, we focused on and successfully synthesized Bi³⁺/Yb³⁺-doped NIR luminescence nanophosphors, RE₂MoO₆:Bi³⁺,Yb³⁺ (RE=Gd, Y, and Lu) and Gd₂Mo_1–xW_xO₆:Bi³⁺,Yb³⁺ (x = 0–0.5), utilizing a solvothermal reaction process. All samples exhibit NIR luminescence of Yb³⁺ ions under ultra-violet (UV) light excitation and broadband excitation due to the charge transfer transition between the O 2p/Bi 6s and Mo 4d or W 5d orbitals, indicated by their optical properties of photoluminescence (PL), PL excitation (PLE), and reflectance spectra. Furthermore, to evaluate the contribution of the Gd₂MoO₆:Bi,Yb (GMO:Bi,Yb) nanophosphor to the conversion efficiency of c-Si, a phosphor-converted film was made using dimethylpolysiloxane (PDMS) and the GMO:Bi,Yb nanophosphor. The results showed that the conversion efficiency of c-Si with the PDMS/GMO:Bi,Yb film is higher than that of c-Si with the PDMS-only film. Based on these results, the utilization of down-shifting nanophosphors is able to enhance the conversion efficiency of c-Si, which could be beneficial in addressing future energy challenges.

中文翻译：

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近红外发光纳米荧光粉 Bi3+/Yb3+ 掺杂的 RE2MoO6 （RE = Gd、Y 和 Lu） 和 Gd2Mo1–xWxO6 的发光调谐


近红外纳米荧光粉因其广泛的应用领域而受到关注，包括晶体硅太阳能电池 （c-Si） 的成分分析、生物成像和太阳光光谱转换器。Yb³⁺ 离子在 1000 nm 左右表现出近红外 （NIR） 发光，这与 c-Si 的第一个生物窗口和最大响应范围一致。因此，我们专注于并成功合成了 Bi³⁺/Yb³⁺ 掺杂的 NIR 发光纳米荧光粉，RE₂MoO₆：Bi³⁺，Yb³⁺（RE=Gd、Y 和 Lu）和 Gd₂Mo_1–xW_xO₆：Bi³⁺，Yb³⁺ （x = 0–0.5），利用溶剂热反应过程。由于 O 2p/Bi 6s 和 Mo 4d 或 W 5d 轨道之间的电荷转移转变，所有样品在紫外 （UV） 光激发和宽带激发下都表现出 Yb³⁺ 离子的 NIR 发光，这由它们的光致发光 （PL）、PL 激发 （PLE） 和反射光谱的光学特性表示。此外，为了评估 Gd₂MoO₆：Bi，Yb （GMO：Bi，Yb） 纳米荧光粉对 c-Si 转换效率的贡献，使用二甲基聚硅氧烷 （PDMS） 和 GMO：Bi，Yb 纳米荧光粉制成了荧光粉转换膜。结果表明，使用 PDMS/GMO：Bi，Yb 薄膜的 c-Si 转换效率高于使用 PDMS 单纯薄膜的 c-Si。基于这些结果，利用下移纳米荧光粉能够提高 c-Si 的转换效率，这可能有利于应对未来的能源挑战。