Visible (VIS) emission and near infrared (NIR) emission enhancement were investigated in yttrium oxy-fluoride (YOF) co-doped with holmium (Ho) and ytterbium (Yb) for potential application in Si solar cells. YOF exhibited stoichiometric rhombohedral phase formation during annealing at 950 °C in air. The surface morphology was examined, as well as how the pyrolysis process affected it, using scanning electron microscopy. A decrease in the VIS emission excited at 447 nm verified the successful energy transfer mechanism from Ho to Yb. The samples’ Ho NIR emission at 1200 nm was noticeably enhanced through co-doping with Yb. Excitation at 924 and 971 nm, resulted in back-energy transfer in the NIR region due to the F + → F + + hν cross-relaxation process. Each measured lifetime fell within the μs range. The calculated critical distance was found to be ∼0.5 nm and ∼0.6 nm for the Blasse and Inokuti-Hirayama models, respectively.

中文翻译：

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Yb3+共掺杂YOF:Ho3+增强近红外发射

研究了共掺杂钬 (Ho) 和镱 (Yb) 的氟氧化钇 (YOF) 的可见光 (VIS) 发射和近红外 (NIR) 发射增强，以期在硅太阳能电池中得到潜在应用。YOF 在 950 °C 空气中退火期间表现出化学计量菱面体相形成。使用扫描电子显微镜检查表面形态以及热解过程对其的影响。447 nm 处激发的 VIS 发射的减少验证了从 Ho 到 Yb 的成功能量转移机制。通过与 Yb 共掺杂，样品在 1200 nm 处的 Ho 近红外发射显着增强。由于 F + → F + + hν 交叉弛豫过程，924 和 971 nm 处的激发导致近红外区域的反能量转移。每个测量的寿命都在 μs 范围内。Blasse 和 Inokuti-Hirayama 模型的计算临界距离分别为 ∼0.5 nm 和 ∼0.6 nm。