磁电流的电荷极化C60-diphenylaminofluorene单添加剂衍生的磁性纳米复合材料的磁电流
Liang Yan1, Min Wang, N P Raju
1Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, USA.
Journal of the American Chemical Society
|February 14, 2012
概括
这项研究使用一种新的纳米复合材料整合了半导体和磁性特性. 该材料在低温和室温下都表现出显著的磁电流 (MC),为先进的混合材料铺平了道路.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 开发具有集成电子和磁性特性的混合材料对于高级功能至关重要.
- 纳米复合材料设计提供了一个多功能平台,可以在纳米尺度上结合不同的材料特性.
研究的目的:
- 设计和描述一个纳米复合材料,集成半导体 (π电子) 和磁性 (d电子) 性能.
- 为了研究设计混合材料的磁电流 (MC) 行为.
主要方法:
- 在一个纳米复合材料中加入一个非局部化的π电子系统 (C60(>DPAF-C9) 和自旋极化d电子 (γ-FeOx纳米粒子).
- 在应用磁场 (0-300 mT) 下,在不同温度 (77 K和 300 K) 下测量磁电流.
主要成果:
- 在C60封装的γ-FeOx纳米粒子中观察到可感知的磁电流 (12%在77K,4.5%在300K).
- 77K的磁电流归因于基于密度的,基于移动性的和合的π-d电子相互作用.
- 确定了在更高温度 (300 K) 中占主导地位的半导体机制.
结论:
- 证明了将π电子和d电子系统结合用于双机制磁电流的可行性.
- 在半导体/磁性混合材料中调节自旋极化和激发状态的指标潜力.
- 强调了这种方法在创建新型功能材料方面所带来的前景.
相关概念视频
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