对高度H2O2/H2O对Al纳米粒子燃烧的影响的原子洞察:ReaxFF分子动力学模拟
Xindong Yu1, Pengtu Zhang2, Heng Zhang1,3
1Key Lab of Colloid and Interface Chemistry, Shandong University, Jinan 250100, China.
Molecules (Basel, Switzerland)
|April 13, 2024
概括
将水添加到纳米粒子 (Al NP) 和过氧化 (H2O2) 推进剂中可以降低燃烧温度. 添加水会影响键形成和分解路径,影响H2的产生和Al NP的稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 计算化学计算化学
背景情况:
- 与过氧化 (H2O2) 结合的纳米粒子 (ANPs) 提供了一个有希望的绿色推进剂替代品.
- 了解ANP与H2O2的燃烧行为对于推进剂的开发至关重要.
- 水作为添加剂对这种燃烧系统的影响需要详细调查.
研究的目的:
- 用分子动力学模拟来研究添加水对Al/H2O2推进剂燃烧的影响.
- 在水的存在下阐明原子级燃烧机制.
- 评估水对反应路径,温度和材料稳定性的影响.
主要方法:
- 使用了反应力场分子动力学 (ReaxFF-MD) 模拟.
- 进行了模拟,将不同比例的水 (H2O) 添加到Al/H2O2系统中.
- 分析的重点是结合形成,热火焰温度和表面相互作用.
主要成果:
- 增加的含水量 (0-30%) 降低了热火焰温度,从4612 K降低到4380 K.
- 添加水改变了债券形成,减少了Al-O债券,增加了ANP上的Al-H债券.
- 无论是H2O2和H2O都在ANP上被吸附和激活,导致基质形成和H2释放,但不会释放O2.
结论:
- 在原子层面上,添加水对Al/H2O2推进剂的燃烧化学有很大影响.
- 有利于Al-O键的形成,有助于氧化的稳定性.
- 氧化物层在ANP上起着极为重要的作用,可以调节H2O2的消耗和H2的产生,同时保持ANP的形态.
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