Institute of Chemistry, Vilnius University, Naugarduko 24, Vilnius LT-03225, Lithuania.
Department of Chemistry, Georgetown University, 37th and O Streets NW, Washington, D.C. 20057, United States.
Inorg Chem. 2023 Jul 10;62(27):10635-10644. doi: 10.1021/acs.inorgchem.3c00913. Epub 2023 Jun 26.
Rare-earth manganese pyrochlores (RMnO) are frustrated magnetic materials, which previously have only been accessed using expensive high-pressure and high-temperature synthesis. In the present work, we demonstrate a convenient synthetic approach to synthesize RMnO pyrochlores at ambient pressure. A series of pyrochlores (R = Y, Ho-Lu) were prepared by a simple and cost-effective molten salt method using NaCl and KCl as the flux. Moreover, phase-selectivity was demonstrated for yttrium manganese oxides (YMnO and YMnO) by a simple variation of synthesis temperature and precursors-to-chlorides ratio. The synthetic procedure does not require high pressures or temperatures nor oxygen flow. All synthesized pyrochlores demonstrated ferromagnetic behavior at low temperature, and the magnetic properties were in good agreement with those of high-pressure-synthesized materials. The versatility of the method was confirmed by the preparation of a mixed-rare earth YErTmYbLuMnO solid solution─a compositionally complex high-entropy oxide.
稀土锰尖晶石（RMnO）是一类具有磁阻特性的材料，过去通常需要采用昂贵的高压高温合成法才能得到。本工作采用一种简便、经济的熔盐法，以 NaCl 和 KCl 为助熔剂，在常压下合成了一系列 RMnO 尖晶石（R = Y、Ho-Lu）。此外，通过简单改变合成温度和前体与氯化物的比例，还实现了钇锰氧化物（YMnO 和 YMnO）的相选择性合成。该合成过程不需要高压、高温或氧气流。所有合成的尖晶石在低温下均表现出铁磁性，其磁性能与高压合成材料吻合良好。通过制备组成复杂的高熵氧化物混合稀土 YErTmYbLuMnO 固溶体，证实了该方法的多功能性。
