在Pb纳米晶体和粘性液态相位之间的可逆相位转换
Wenjing Zheng1, Jun Kang2,3, Kaiyang Niu4
1School of Energy and Power Engineering, North University of China, Taiyuan 030051, China.
Science advances
|June 19, 2024
概括
研究人员观察到 (Pb) 纳米晶体和类似液体相之间的可逆相变. 这项使用先进显微镜实现的发现,为在电子束下材料的行为提供了新的见解.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 物理化学 物理化学
背景情况:
- 阶段转换在材料科学中至关重要,但对研究具有挑战性,特别是当由固体-液体反应诱导时.
- 了解这些转换的机制对于基础科学和应用工程都至关重要.
研究的目的:
- 研究和描述金属纳米晶体和类似液态相之间的可逆相变.
- 在特定条件下阐明驱动这些转变的机制.
主要方法:
- 在现场使用液体细胞传导电子显微镜 (LC-TEM) 来实时观察转换.
- 电子电流密度被调节以诱导和控制可逆相变.
- 密度函数理论 (DFT) 和分子动力学 (MD) 的计算用于支持实验观测.
主要成果:
- 成功地证明了 (Pb) 纳米晶体和粘性液态相之间的可逆相变.
- 这些转换是由变化的电子电流密度 (10003000 e- Å−2 s−1) 控制的.
- 液态相表现出短距离的序列,Pb-Pb距离为0.5nm,被确定为金属有机产物.
结论:
- 粘性液态相由Pb与CH3O碎片在电子束辐射下来自三乙烯甘醇溶液的反应产生的.
- 这项研究揭示了金属纳米晶体中可逆相变的新型机制.
- 这些发现表明材料工程和纳米技术的潜在广泛应用.
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