EurOgels：<em>通过</em>混合纳米棒的组装制备的具有多孔结构的铁磁半导体<a href="#fn1" title="提供电子补充信息（ESI）：实验详细信息和其他分析数据。参见DOI：10.1039 / c8nr06536e">†</a>,Nanoscale

当前位置： X-MOL 学术 › Nanoscale › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

EurOgels：通过混合纳米棒的组装制备的具有多孔结构的铁磁半导体 †
Nanoscale ( IF 6.7 ) Pub Date : 2018-09-25 00:00:00 , DOI: 10.1039/c8nr06536e
Bastian Trepka _{1,

2,

3} , Julian Stiegeler _{1,

2,

3} , Ilona Wimmer _{1,

2,

3} , Mikhail Fonin _{1,

2,

3} , Sebastian Polarz _{1,

2,

3}

Affiliation

EuO是独特的，因为它属于结合了半导性性质（E_间隙= 1.1 eV）和天然铁磁性的少数固体。对于EuO的未来应用，例如自旋过滤器或传感器，必须学习如何制备确定的纳米结构。与其他陶瓷氧化物不同，目前尚无针对EuO纳米材料（例如多孔材料）的已建立的软化学路线（例如，溶胶-凝胶）。这是由于氧化态Eu（+ II）的不稳定性质。我们提出一种导致EuO气凝胶的基于粒子的方法。我们使用有机-无机杂化相（Eu ₂ O ₃–苯甲酸酯）并将其组装成气凝胶，然后转化为纯相EuO。结果表明，有机醛可作为封端剂来控制杂化颗粒的形貌。根据醛的空间需求，获得纵横比增加的板状颗粒或纳米棒。当长宽比增加到> 20时，颗粒形成凝胶。超临界干燥后，将获得基于纳米棒的气凝胶。用Eu-蒸气处理后者会导致在保留气凝胶结构的同时将Eu ₂ O ₃结构域还原为EuO。通过SQUID测量可提供所得EuO气凝胶中的铁磁性证明。

"点击查看英文标题和摘要"

EurOgels: A ferromagnetic semiconductor with a porous structure prepared via the assembly of hybrid nanorods†

EuO is unique, because it belongs to the few solids combining semiconducting properties (E_gap = 1.1 eV) with native ferromagnetism. For future applications of EuO, e.g. as spin-filters or for sensors, one has to learn how defined nanostructures can be prepared. Unlike other ceramic oxides, there are no established soft-chemistry routes (e.g. sol–gel) towards EuO nanomaterials e.g. porous materials. This is due to the labile nature of the oxidation state Eu(+II). We present a particle-based method leading to a EuO aerogel. Instead of making the target material directly, we use nanoparticles of an organic–inorganic hybrid phase (Eu₂O₃–benzoate) and assemble those into an aerogel, followed by the transformation into phase-pure EuO. It is shown that organic aldehydes act as capping agents for controlling the morphogenesis of the hybrid particles. Depending on the steric demand of the aldehyde, one obtains plate-like particles or nanorods with increasing aspect ratio. The particles form a gel, when the aspect ratio is increased to >20. After supercritical drying, one receives a nanorod-based aerogel. Treatment of the latter with Eu-vapor leads to reduction of the Eu₂O₃ domains to EuO while retaining the aerogel structure. Proof of ferromagnetism in the resulting EuO aerogel was delivered by SQUID measurements.

更新日期：2018-09-25

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南

全部期刊列表>>