Liang Xuan, Yamaura Kazunari, Belik Alexei A
Research Center for Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS), Namiki 1-1, Tsukuba, Ibaraki, 305-0044, Japan.
Graduate School of Chemical Sciences and Engineering, Hokkaido University, North 10 West 8, Kita-ku, Sapporo, Hokkaido, 060-0810, Japan.
Chemistry. 2024 Jul 19;30(41):e202401960. doi: 10.1002/chem.202401960. Epub 2024 Jul 1.
Cation order, which can be controlled by synthesis conditions and stoichiometry, plays an important role in properties of perovskite materials. Here we show that aliovalent doping by Sb in SmMnMn(MnSb)O quadruple perovskite solid solutions can control cation orders in both A and B sites. Samples with 0.4≤x≤2 were synthesized by a high-pressure, high-temperature method at 6 GPa and 1770 K. Three regions with different cation orders were found at 0.5≤x≤1.0, x=1.5-1.6, and x=1.8. The 0.5≤x≤1.0 compositions have a B-site-disordered and A-site columnar-ordered structure with space group P4/nmc; the x=1.5 and 1.6 samples have a B-site rock-salt-ordered and A-site columnar-ordered structure with space group P4/n; the x=1.8 sample has a B-site rock-salt-ordered and A-site-disordered structure with space group P2/n. All the samples show one ferrimagnetic transition: T increases from 35 K to 73 K for 0.5≤x≤1.0, T=81 K for x=1.5 and 1.6, and T=53 K for x=1.8.
阳离子排序可通过合成条件和化学计量比来控制，在钙钛矿材料的性能中起着重要作用。在此我们表明，在SmMnMn(MnSb)O四重钙钛矿固溶体中用Sb进行异价掺杂可控制A位和B位的阳离子排序。通过在6 GPa和1770 K的高压高温方法合成了0.4≤x≤2的样品。在0.5≤x≤1.0、x = 1.5 - 1.6和x = 1.8时发现了三个具有不同阳离子排序的区域。0.5≤x≤1.0的组成具有B位无序和A位柱状有序结构，空间群为P4/nmc；x = 1.5和1.6的样品具有B位岩盐有序和A位柱状有序结构，空间群为P4/n；x = 1.8的样品具有B位岩盐有序和A位无序结构，空间群为P2/n。所有样品都显示出一个亚铁磁转变：对于0.5≤x≤1.0，转变温度T从35 K增加到73 K；对于x = 1.5和1.6，T = 81 K；对于x = 1.8，T = 53 K。
