月球真空下超快激光LIBS的岩土成分检测方法研究

Space has always been mysterious for human beings. With the landing of "Yutu No. 2", China has shown the world that space exploration is endless. At present, the data of the moon obtained by infrared remote sensing and other technologies revealed that the main components of the lunar geotechnical soil are oxygen, silicon, iron, calcium, aluminum, and also rich in 3He resources. Therefore, to detect the soil and rock in the moon more accurate in a small range is significant. In the lunar vacuum environment, the traditional detection method is difficult to use due to the high degree of vacuum. Under the circumstances, the LIBS (laser-induced breakdown spectroscopy) technique with remote detection capability, rapid detection capability, and light element detection capability shows its advantages. This project intends to study the detection of soil and rock by laser induced breakdown spectroscopy under lunar vacuum ambient, we propose to study the plasma source and spectral enhancement method. On the one hand, it will study the dynamic characteristics of ultrafast laser induced plasma and its different elemental spectra under lunar vacuum. On the other hand, based on the temporal and spatial distribution characteristics of plasma under lunar vacuum, a method of resonance excitation using wavelength tunable laser will be studied. On this basis, the method will be applied to analyze the element components of geotechnical samples and establish a lunar environment database of interested elements.

太空对于人类而言一直是神秘而又令人向往的，随着“玉兔二号”的登月，我国向世界表明：太空探索永无止境。目前通过红外遥感等技术对月球进行大范围探测发现月球岩土的主要成分是氧、硅、铁、钙、铝，此外还含有丰富的3He资源，因此未来对月球岩土成分进行小范围更精细的检测十分重要。而在月球真空环境下，传统的检测方法难以适应，具有非接触具有远程探测能力，快速检测能力，轻量元素检测能力的激光诱导击穿光谱光谱技术便凸显了自身的优势。本项目拟研究月球真空条件下，LIBS对岩土成分的快速分析方法，具体从等离子体源研究和光谱增强方法入手，一方面研究低至月球真空度下超快激光等离子体及其中不同元素光谱的动力学特性。另一方面研究基于月球真空度下等离子体的时空分布特性，使用波长可调谐激光共振激发增强谱线的方法。在此基础上，将本方法用于模拟岩土样品的特征元素成分分析并建立相应元素的月球环境数据库。

近年来，我国在太空探测领域持续发力，在近地、月球与火星都留下了我们的探索痕迹，相应的远程物质成分分析技术也得到了应用。其中激光诱导光谱技术（LIBS）显示了其极大地应用前景。本项目针对太空探测中对元素探测的应用需求，研究了不同气氛，真空度环境下的LIBS的光谱特性。重点研究了H,He,O,C,W等有机无机元素在真空腔中的时间分辨发射光谱，这将为太空环境探测中的元素检测提供可靠的基础数据。与此同时，我们还研究了不同材料在不同气氛条件下的烧蚀率，实验获得的10-100nm级的单脉冲烧蚀率为材料分析中的逐层分析提供了可能，有望在微区分析中提供一种新的工具。