氧化行为和原子结构转换的尺寸选择的凝聚电阻纳米集群
Shengyong Hu1,2, Kuojuei Hu1,2, Yongxin Zhang1,2
1National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, School of Physics, Nanjing University, Nanjing 210093, People's Republic of China.
Nanotechnology
|April 30, 2024
概括
尺寸选择的 (TaN) 集群表现出热稳定性和氧化诱导的无形化. 在低于预期的温度下,回火恢复了有序的结构,较小的集群形成了独特的形状.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 表面科学是一门学科.
背景情况:
- (Ta) 集群因其独特的特性而引起人们的兴趣.
- 了解它们在氧化和热应力下的行为对于应用至关重要.
研究的目的:
- 为了研究大小选择的集群 (TaN) 的热稳定性和氧化行为.
- 探索烧结,结晶和在化后的结构修复过程.
主要方法:
- 气相冷凝集束光束源带有质量选择器用于尺寸选择.
- 偏差校正扫描传输电子显微镜 (AC-STEM) 用于成像.
- 用于化学分析的X射线光电子光谱 (XPS) 和能量分散光谱 (EDS).
- 在现场加热技术用于观察动态过程.
主要成果:
- TaN集群表现出良好的热稳定性.
- 氧化导致无形化,Ta主要处于+5氧化状态,最大氧化深度为5nm.
- 尺寸依赖的烧结和结晶发生在明显低于点的温度下.
- 排序结构,包括小集群中的十面体和二面体形式,在回火时被恢复.
- 较大的集群形成类似于晶体Ta2O5膜的结构.
- 修复后的结构至少在6个月内保持稳定.
结论:
- 集群可以可控地合成,并描述它们的热和氧化行为.
- 化为氧化集群在惊人的低温下恢复有序结构提供了一条途径.
- 观察到的大小依赖的结构进化为纳米粒子形成和稳定性提供了洞察力.
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