通过N-Doped石墨碳层稳定硬磁性SmCo5纳米粒子
Zhenhui Ma1,2, Ming Yue2, Hu Liu1
1Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States.
Journal of the American Chemical Society
|April 18, 2020
概括
我们开发了一种方法来制造大小可控的Samarium Cobalt (SmCo5) 纳米粒子, 用添加的石墨碳 (NGC) 保护它们以防止氧化. 这些稳定的SmCo5/NGC纳米粒子在各种温度下显示出高性能纳米磁铁应用的潜力.
科学领域:
- 材料科学
- 纳米技术
- 化学学
背景情况:
- (SmCo5) 纳米粒子对于高性能磁铁至关重要.
- 空气氧化对SmCo5纳米颗粒的稳定性和性能构成重大挑战.
- 控制纳米粒子大小对于定制磁性属性至关重要.
研究的目的:
- 开发一种合成可控制大小的SmCo5纳米粒子的化学方法.
- 通过用添加的石墨碳 (NGC) 涂层来稳定SmCo5纳米颗粒对空气氧化.
- 评估用于纳米磁体应用的合成SmCo5/NGC纳米粒子的磁性和稳定性.
主要方法:
- 最初的CoO和Sm2O3纳米粒子的合成.
- 在反向微粒中聚合,形成控制尺寸的SmCo-氧化物纳米粒子 (110,150,200 nm).
- 用聚多巴胺涂层,热成SmCo-O/NGC纳米颗粒,嵌入CaO,并在850°C下用Ca进行降解以获得SmCo5/NGC纳米颗粒 (80,120和180nm).
主要成果:
- 通过10纳米NGC层成功合成可控制大小的SmCo5纳米粒子.
- 在室温和100°C时,NGC涂层有效地稳定了SmCo5纳米颗粒.
- 在室温暴露5天后,180nmSmCo5/NGC纳米粒子的磁化保持稳定 (86.1emu/g).
- 观察到高强制性 (Hc) 在150K时为51.1kOe,在330K时为21.9kOe,其余量 (Mr) 稳定在84.8emu/g左右.
结论:
- 已经证明了一种合成和稳定SmCo5纳米粒子的新方法.
- 这种NGC涂层能很好地防止空气氧化,并保持磁性.
- 稳定的SmCo5/NGC纳米粒子适用于广泛的温度范围内的高性能纳米磁体应用.
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