对变态无形-AlOx (2.5 < x ≤ 3.0) 纳米结构转化为晶多态的固态相位过渡的动态分析
Elijah M Davis1,2, Claudia Rawn3, Matthew G Boebinger4
1Department of Chemical & Biomolecular Engineering, University of Tennessee, Knoxville, TN, USA.
Scientific reports
|March 6, 2025
概括
我们研究了无形氧化 (m-AlOx@C) 纳米复合材料的相变动力学. 过渡到稳定的化相遵循体积收缩模型,激活能量屏障为~270kJ/mol.
科学领域:
- 材料科学 材料科学 材料科学
- 化学动力学 化学动力学
- 纳米技术纳米技术
背景情况:
- 固体-固体相变材料 (SS-PCM) 对于储能至关重要,但它们的相变动力学知之甚少.
- 在SS-PCM中捕获转移稳定相具有挑战性,阻碍了动力学研究.
- 无形氧化 (m-AlOx@C) 纳米颗粒以前使用激光除合成溶液 (LASiS) 进行合成.
研究的目的:
- 在m-AlOx@C纳米复合材料中进行第一个固体-固体相变的化学动力学分析.
- 为了研究从元稳定的m-AlOx@C到半稳定的化相 (θ/γ-Al2O3) 的相变.
- 为了确定这个阶段过渡的激活能量屏障.
主要方法:
- 通过溶液中的激光废弃合成 (LASiS) 合成m-AlOx@C纳米复合材料.
- 温度依赖的X射线衍射 (XRD) 研究,以分析相位过渡.
- 收缩体积动力学模型和阿雷尼乌斯图形分析的应用.
主要成果:
- 从m-AlOx@C到 θ/γ-Al2O3的相位过渡遵循一个收缩体积动力学模型.
- m-AlOx结构的原子密度明显低于最后的Al2O3阶段,证实了体积收缩.
- 阿雷尼乌斯图形分析得出了大约270±11kJ/mol的激活能量屏障,用于相位过渡.
结论:
- 这项研究提供了第一个化学动力学分析,用于金属稳定的m-AlOx@C纳米复合材料的固体-固体相变.
- 阶段过渡受收缩体积动力学模型的控制,与体积收缩相一致.
- 确定的激活能量屏障与微米大小的颗粒氧化相比较.
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