火焰喷雾热解合成因其设备紧凑、装置简单,非常适用于地外原位资源利用,有助于实现未来可持续的深空探索。其中微爆现象能促进气相转化路径,从而形成粒径均匀、纯度高的纳米颗粒。本研究设计了一种安装在多元扩散平焰燃烧器内的单液滴发生装置,结合阴影成像法研究单液滴的燃烧微爆行为。实验以硝酸铝/乙醇为前驱物、二乙基己酸为添加剂,探究不同添加剂浓度和火焰温度下液滴的微爆特性。结果表明液滴的微爆概率随着温度升高及添加剂浓度增大而提高。此外发现前驱体中的液相反应对微爆发生具有促进作用。该装置设计与初步研究结果将将有效揭示高温燃烧条件下液滴燃烧微爆机制,为火焰合成过程的精准调控奠定关键性基础。
Flame spray pyrolysis, benefitted from its compact equipment and straightforward setup, is well‑suited for in‑situ resource utilization in extraterrestrial environments, supporting sustainable deep‑space exploration. The micro‑explosion phenomenon in the flame-synthesis process promotes gas‑phase transformation, enabling the production of uniform, high‑purity functional nanoparticles. In this study, a single‑droplet generator integrated into a multi‑element diffusion flat‑flame burner was designed and combined with high‑speed shadowgraph technique to investigate the micro‑explosion of precursor droplets traversing the flame front. Using aluminum nitrate as the precursor, ethanol as the solvent, and 2‑ethylhexanoic acid as the additive, the micro‑explosion behavior was examined at varying additive concentrations and flame temperatures. The results show that the probability of micro‑explosion increases with higher flame temperatures and higher additive concentrations. Furthermore, liquid‑phase reactions within the precursor were found to promote micro‑explosion. This study aimed to systematically elucidate the core mechanisms of droplets micro-explosion and pave ways for precise control of atomized flame synthesis.
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