Abstract Design and synthesis of new fluoride upconversion (UC) luminescent materials with controllable morphologies remains a challenge. Here, novel Ba4Bi3F17:Er3+/Yb3+ UC nanoparticles (UCNPs) were discovered and prepared using a simple one-step solvothermal strategy, and the modulation of the morphology and particle size was investigated in detail. Upon 980 nm excitation, the influence of dosage amounts of Yb3+/Er3+, and the environmental temperatures on the UC luminescent performance were studied in the temperature range of 293–393 K. The maximum relative sensitivities (Sr) of Ba4Bi3F17:1 mol%Er, 13 mol%Yb material are calculated to be 0.0122 K-1 and 0.0167 K−1 at 293 K, respectively, based on the two energetic levels of (2H11/2, 4S13/2) and (2H11/2, 4F9/2). In addition, the internal heating performance of the Ba4Bi3F17:Er3+/Yb3+ UCNPs was also evaluated in the pump power range of 112–901 mW, and the internal temperature of the UCNPs increased from 296 to 367 K with the increase of excitation power. This work initiates the discovery of the new bismuth-based fluoride nanothermometers and demonstrates the great potential for bifunctional applications in temperature sensing and optical heater devices.

中文翻译：

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Ba4Bi3F17:Er3+,Yb3+的形态控制合成及双功能温度传感和光学加热应用

摘要 具有可控形态的新型氟化物上转换 (UC) 发光材料的设计和合成仍然是一个挑战。在这里，使用简单的一步溶剂热策略发现并制备了新型 Ba4Bi3F17:Er3+/Yb3+ UC 纳米粒子 (UCNPs)，并详细研究了形态和粒径的调节。在980 nm激发下，在293-393 K的温度范围内研究了Yb3+/Er3+用量和环境温度对UC发光性能的影响。 Ba4Bi3F17的最大相对灵敏度（Sr）：1 mol%Er , 基于 (2H11/2, 4S13/2) 和 (2H11/2, 4F9/2) 的两个能级，13 mol% Yb 材料在 293 K 时分别计算为 0.0122 K-1 和 0.0167 K-1 ）。另外，Ba4Bi3F17的内热性能：Er3+/Yb3+ UCNPs 也在 112-901 mW 的泵浦功率范围内进行了评估，随着激发功率的增加，UCNPs 的内部温度从 296 K 增加到 367 K。这项工作启动了新的基于铋的氟化物纳米温度计的发现，并展示了在温度传感和光学加热器设备中双功能应用的巨大潜力。