The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
J Am Chem Soc. 2011 Aug 31;133(34):13296-9. doi: 10.1021/ja2057314. Epub 2011 Aug 4.
We report the growth of NaCl-type binary nanocrystal (NC) superlattice membranes by coassembly of FePt and MnO NCs at the liquid-air interface. The constituent FePt NCs were converted into the hard magnetic L1(0) phase by thermal annealing at 650 °C without degradation of the long-range NC ordering. In contrast, both FePt-only NC superlattices and FePt-MnO disordered NC mixtures showed substantial FePt sintering under the same annealing conditions. Our results demonstrate that the incorporation of FePt NCs into binary superlattices can solve the problems of FePt sintering during conversion to the L1(0) phase, opening a new route to the fabrication of ordered ferromagnetic NC arrays on a desired substrate for high-density data storage applications.
我们通过在液-气界面处共组装 FePt 和 MnO NCs 来报告 NaCl 型二元纳米晶体（NC）超晶格膜的生长。在 650°C 下进行热退火，组成的 FePt NCs 被转化为硬磁 L1(0)相，而长程 NC 有序性没有降解。相比之下，在相同的退火条件下，FePt 仅 NC 超晶格和 FePt-MnO 无序 NC 混合物都显示出大量的 FePt 烧结。我们的结果表明，将 FePt NCs 掺入二元超晶格中可以解决在转化为 L1(0)相时 FePt 烧结的问题，为在所需基底上制造有序铁磁 NC 阵列以用于高密度数据存储应用开辟了一条新途径。
