Douzi Abir, Slimi Sami, Madirov Eduard, Serres Josep Maria, Solé Rosa Maria, Ben Salem Ezzedine, Turshatov Andrey, Richards Bryce S, Mateos Xavier
Universitat Rovira i Virgili (URV), Física i Cristal·lografia de Materials (FiCMA) Marcel·li Domingo 1 Tarragona 43007 Spain
I.P.E.I. of Monastir, Research Laboratory: Physico-chemistry of Innovative Materials LR24ES16, University of Monastir 5019 Tunisia.
RSC Adv. 2025 Jun 10;15(25):19623-19639. doi: 10.1039/d5ra01912e.
Dy-doped CaLa(SiO)(PO)O (CLSPO) phosphors were synthesized a solid-state reaction method and characterized for their structural, optical, and thermometric properties. X-ray diffraction (XRD) and Rietveld refinement confirmed a hexagonal apatite-type structure (6/) with refined lattice parameters of = = 9.604(3) Å, = 7.103(1) Å. First-principles calculations for the undoped crystal revealed a direct bandgap of 4.08 eV, confirming CLSPO as a suitable host material for luminescent applications. Photoluminescence spectra exhibited characteristic Dy emissions, with two blue bands ( : 468 nm, : 479 nm) and two yellow bands ( : 543 nm, : 575 nm). The yellow-to-blue (/) intensity ratio displayed a strong temperature dependence, establishing CLSPO:Dy as a promising candidate for luminescence-based thermometry. The optimal Dy doping concentration was determined to be 3 at%, beyond which concentration quenching effects were observed. Photoluminescence studies further demonstrated that electric dipole-dipole interactions govern the dominant energy transfer mechanism, as evidenced by concentration-dependent quenching behavior. The absolute photoluminescence quantum yield (PLQY) was 5.7%, and Arrhenius analysis determined an activation energy of 0.11 eV. The decay time decreases with increasing Dy concentration (from 658 μs at 0.5 at% Dy to 252 μs at 10 at%). The fluorescence intensity ratio (FIR) method for optical thermometry revealed an absolute sensitivity ( ) of 3.27 10 K at 298 K, while the repeatability () of the / ratio exhibited a reproducibility of 95.88% at 298 K, ensuring consistent and reliable temperature sensing performance. Furthermore, the luminescence remained stable over three hours of multiple heating-cooling cycles (298-523 K), confirming excellent photostability and reversibility. These results establish CLSPO:Dy phosphors as highly efficient, thermally stable, and optically robust materials for next-generation temperature sensors, solid-state lighting, and advanced photonic applications.
采用固相反应法合成了Dy掺杂的CaLa(SiO)(PO)O (CLSPO)荧光粉，并对其结构、光学和测温性能进行了表征。X射线衍射(XRD)和Rietveld精修证实了其六方磷灰石型结构(6/)，精修后的晶格参数为 = = 9.604(3) Å， = 7.103(1) Å。对未掺杂晶体的第一性原理计算表明其直接带隙为4.08 eV，证实CLSPO是一种适用于发光应用的基质材料。光致发光光谱显示出Dy的特征发射，有两个蓝带( : 468 nm， : 479 nm)和两个黄带( : 543 nm， : 575 nm)。黄蓝(/)强度比表现出强烈的温度依赖性，表明CLSPO:Dy是基于发光测温的有前途的候选材料。确定最佳Dy掺杂浓度为3 at%，超过该浓度会观察到浓度猝灭效应。光致发光研究进一步表明，电偶极-偶极相互作用主导能量转移机制，浓度依赖性猝灭行为证明了这一点。绝对光致发光量子产率(PLQY)为5.7%，Arrhenius分析确定激活能为0.11 eV。衰减时间随Dy浓度增加而减小(从0.5 at% Dy时的658 μs降至10 at%时的252 μs)。用于光学测温的荧光强度比(FIR)方法在298 K时的绝对灵敏度( )为3.27×10 K，而/比的重复性()在298 K时的再现性为95.88%，确保了一致且可靠的温度传感性能。此外，在多个加热-冷却循环(298 - 523 K)的三小时内发光保持稳定，证实了优异的光稳定性和可逆性。这些结果表明CLSPO:Dy荧光粉是用于下一代温度传感器、固态照明和先进光子应用的高效、热稳定且光学稳健的材料。
