A novel layered transparent Er:CaF₂ composite ceramic was proposed in the present study. Er:CaF₂ nanoparticles were synthesized by a chemical coprecipitation method. The crystal structures and morphologies of synthesized nanoparticles were performed by X‐ray diffraction (XRD) and field emission scanning electron microscope (FE‐SEM) measurements, respectively. Transparent composite ceramic was fabricated by the combination of multistep dry pressing and hot‐pressed sintering method without any sintering aids or binders. The average grain size of 2% Er‐doped and 5% Er‐doped layers were about 30 and 55 μm, respectively. The thickness of interfacial between two different Er‐doped layers was 150‐200 μm. For a 1.5 mm thickness transparent Er:CaF₂ composite ceramic, the optical transmittance reached 44.9% at 500 nm and 53.6% at 1200 nm. The luminescence spectra and thermal conductivities of transparent ceramic specimens were also discussed.

中文翻译：

---

透明Er：CaF2复合陶瓷的制备与微观结构表征

本研究提出了一种新型的层状透明Er：CaF ₂复合陶瓷。通过化学共沉淀法合成了Er：CaF ₂纳米粒子。分别通过X射线衍射（XRD）和场发射扫描电子显微镜（FE-SEM）测量来执行合成纳米颗粒的晶体结构和形态。透明复合陶瓷是通过多步干压和热压烧结方法相结合而制成的，没有任何烧结助剂或粘结剂。2％的Er掺杂层和5％的Er掺杂层的平均晶粒尺寸分别约为30和55μm。两个不同的掺Er层之间的界面厚度为150-200μm。对于1.5毫米厚的透明Er：CaF ₂复合陶瓷，在500 nm处的透光率达到44.9％，在1200 nm处的透光率达到53.6％。还讨论了透明陶瓷样品的发光光谱和热导率。