Abstract Rhabdophane-type Eu3+,Tb3+-codoped LaPO4·nH2O single-crystal nanorods with the compositions La0.99999-xEuxTb0.00001PO4·nH2O (x = 0–0.03), La0.99999-yTbyEu0.00001PO4·n′H2O (y = 0–0.010), and La0.99999-zTbzEu0.000007PO4·n′′H2O (z = 0–0.012) were hydrothermally synthesized with microwaves. It is shown that the Eu3+,Tb3+ codoping does not affect the thermal stability of these nanorods, which is due to the formation of substitutional solid solutions with both Eu3+ and Tb3+ replacing La3+ in the crystal lattice. Moreover, it is also shown that monazite-type Eu3+,Tb3+-codoped LaPO4 single-crystal nanorods can be obtained by calcining their rhabdophane-type Eu3+,Tb3+-codoped LaPO4·(n,n′ or n′′)H2O counterparts at moderate temperature in air, and that they are thermally stable. It is also observed that, for the same Eu3+,Tb3+-codoping content, the monazite-type Eu3+,Tb3+-codoped LaPO4 nanorods exhibit higher photoluminescent efficiency than the rhabdophane-type Eu3+,Tb3+-codoped LaPO4· (n,n′ or n′′)H2O nanorods. Moreover, it is found that the highest photoluminescence emission corresponds to the monazite-type La0.96999Eu0.02Tb0.00001PO4 nanorods for the La0.99999-xEuxTb0.00001PO4 system. However, for those compositions energy transfer from Tb3+ to Eu3+ does not occur. In addition, for an efficient energy transfer to occur, a content of at least 1 mol% Tb3+ is needed in all the studied materials.

中文翻译：

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微波水热合成Eu 3+ ,Tb 3+ 共掺杂LaPO 4 ∙ n H 2 O 和LaPO 4 纳米棒的结构-微观结构表征和光学性质

摘要 Rhabdophane 型 Eu3+,Tb3+ 共掺杂 LaPO4·nH2O 单晶纳米棒，其组成为 La0.99999-xEuxTb0.00001PO4·nH2O (x = 0–0.03), La0.99999-yTby'Eu0.000.000 0–0.010) 和 La0.99999-zTbzEu0.000007PO4·n''H2O (z = 0–0.012) 是用微波水热合成的。结果表明，Eu3+、Tb3+ 共掺杂不影响这些纳米棒的热稳定性，这是由于形成了置换固溶体，Eu3+ 和 Tb3+ 都取代了晶格中的 La3+。此外，还表明独居石型 Eu3+,Tb3+ 共掺杂的 LaPO4 单晶纳米棒可以通过在中等温度下煅烧其弹纹烷型 Eu3+,Tb3+ 共掺杂的 LaPO4·(n,n' 或 n'')H2O 对应物来获得。空气中的温度，并且它们是热稳定的。还观察到，对于相同的 Eu3+,Tb3+-共掺杂含量，独居石型 Eu3+,Tb3+ 共掺杂的 LaPO4 纳米棒比斜纹石型 Eu3+,Tb3+ 共掺杂的 LaPO4·(n,n' 或 n'')H2O 纳米棒表现出更高的光致发光效率。此外，发现最高的光致发光发射对应于 La0.99999-xEuxTb0.00001PO4 系统的独居石型 La0.96999Eu0.02Tb0.00001PO4 纳米棒。然而，对于那些组合物，不会发生从 Tb3+ 到 Eu3+ 的能量转移。此外，为了发生有效的能量转移，所有研究的材料中至少需要 1 mol% Tb3+ 的含量。用于 La0.99999-xEuxTb0.00001PO4 系统的 00001PO4 纳米棒。然而，对于那些组合物，不会发生从 Tb3+ 到 Eu3+ 的能量转移。此外，为了发生有效的能量转移，所有研究的材料中至少需要 1 mol% Tb3+ 的含量。用于 La0.99999-xEuxTb0.00001PO4 系统的 00001PO4 纳米棒。然而，对于那些组合物，不会发生从 Tb3+ 到 Eu3+ 的能量转移。此外，为了发生有效的能量转移，所有研究的材料中至少需要 1 mol% Tb3+ 的含量。