A series of Er³⁺‐doped GdPO₄ phosphors was synthesized using a conventional solid‐state reaction. The monazite structure (space group P12₁/n₁) of the obtained materials was confirmed using X‐ray diffraction and Fourier transform infrared spectroscopy. Their optical spectra (excitation, emission, absorption, decay curves) were measured at room temperature in the visible and near‐infrared (NIR) regions. The UV–visible–NIR optical absorption spectrum of GdPO₄:7% Er³⁺ was analyzed based on Judd–Ofelt (J–O) theory and the J–O intensity parameter (Ω₂, Ω₄, Ω₆) was calculated. J–O intensity parameters were used to evaluate spontaneous emission properties such as branching ratios, transition probabilities, and radiative lifetime. The calculated quantum efficiency of the 1.5 μm emission (⁴I_13/2−⁴I_15/2) was calculated to be 89%. This result proved that GdPO₄:Er³⁺ is suitable for use in optical amplifiers and is a potential host for laser applications. The most interesting transitions, located at about 540 nm, and 1.0 and 1.5 μm were investigated as a function of doping level and of temperature, to assess the conditions needed for the highest emission performance and to explore the range of application, in particular in the fields of lighting, thermal sensing, and of phosphors for bio‐imaging.

中文翻译：

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GdPO4：Er3的合成，表征和光谱学。

使用常规的固态反应合成了一系列掺Er ^3+的GdPO ₄荧光粉。使用X射线衍射和傅里叶变换红外光谱法确定了所得材料的独居石结构（空间群P12 ₁ / n ₁）。在室温下在可见光和近红外（NIR）区域中测量了它们的光谱（激发，发射，吸收，衰减曲线）。GdPO的紫外-可见-近红外光吸收光谱₄：7％铒³⁺根据Judd-Ofelt理论（J-O）理论和J-ø强度参数（Ω分析₂，Ω ₄，Ω ₆）进行了计算。J–O强度参数用于评估自发发射特性，例如分支比，跃迁几率和辐射寿命。1.5微米发射（计算出的量子效率⁴我_13/2 - ⁴我_15/2）经计算为89％。该结果证明了GdPO ₄：Er ³⁺适用于光放大器，是激光应用的潜在宿主。研究了最有趣的跃迁（约540 nm，1.0和1.5μm）与掺杂水平和温度的函数关系，以评估实现最高发射性能所需的条件并探索应用范围，尤其是在照明，热传感和生物成像荧光粉领域。