We investigated the luminescent properties of Ho³⁺ and Yb³⁺ co-doped AZrO₃ (A = Ca, Sr, and Ba) perovskite nanocrystals synthesized using a combustion method. X-ray diffraction measurement revealed that these nanocrystals exhibited differences in their structural symmetries, varying from orthorhombic in CaZrO₃ to cubic in BaZrO₃, with an increase in their grain sizes and an enhanced degree of crystallinity along increased post-annealing temperatures. Under near-infrared excitations, we observed strong green (545 nm) and weak red (660 nm) emissions from the Ho³⁺ ions. Interestingly, the smaller the sizes of the A ions, the stronger were the upconversion emissions and the greater was the increase in the emission intensity due to post-annealing. We found that the crystal symmetry and the degree of crystallinity of the host play an important role in determining the luminescent behavior of Ho³⁺ ions in perovskite nanocrystals.

^{我们研究了使用燃烧法合成的 Ho 3+}和 Yb ³⁺共掺杂的 A ZrO ₃ ( A  = Ca、Sr 和 Ba) 钙钛矿纳米晶体的发光特性。X 射线衍射测量表明，这些纳米晶体在结构对称性方面表现出差异，从 CaZrO ₃中的斜方晶格到 BaZrO ₃中的立方晶格，随着后退火温度的增加，它们的晶粒尺寸增加，结晶度提高。在近红外激发下，我们观察到来自 Ho ³⁺离子的强绿色 (545 nm) 和弱红色 (660 nm) 发射。有趣的是， A的尺寸越小离子，上转换发射越强，由于后退火导致的发射强度增加越大。我们发现主体的晶体对称性和结晶度在决定钙钛矿纳米晶体中Ho ^{3+离子的发光行为中起重要作用。}