2025年"核理安邦“联合博士生学术论坛

The signal quality improvement of laser-induced breakdown spectroscopy due to the microwave plasma torch modulation

Not scheduled

12m

Location: 清华大学核能与新能源技术研究院

口头报告 核技术与应用、医学物理与工程 核技术与应用、医学物理与工程

Speaker

炳玉 魏 (兰州大学)

摘要

我们提出了一种新的方法，通过将微波等离子体炬（MPT）与激光诱导击穿光谱（LIBS）结合，称为MPT-LIBS，有效解决了传统LIBS的局限性。使用低激光脉冲能量为0.55毫焦的铜样品对MPT-LIBS技术进行了评估。结果显示，Cu I 521.82纳米线的增强因子超过70，而Cu I 324.75纳米和327.40纳米线的增强因子超过了两个数量级。此外，所有铜谱线的相对标准偏差（RSD）均有所降低，特别是Cu I 521.82纳米线，从11.48%降低到1.36%，这表明信号稳定性显著提高。利用共聚焦显微镜对测试样品进行表征发现，MPT-LIBS的剥蚀区域仅为LIBS的1.36倍。Cu I 324.75纳米线的检出限从52.8 ppk降低到319 ppm。

Abstract

Here, we present a novel approach by integrating microwave plasma torch (MPT) with LIBS, referred to as MPT-LIBS, which effectively addresses the limitations associated with traditional LIBS. The MPT-LIBS technique is evaluated using Cu samples with a low laser pulse energy of 0.55 mJ. A remarkable enhancement factor of over 70 for Cu I 521.82 nm line is demonstrated, while that of Cu I 324.75 nm and 327.40 nm lines exceeding two orders of magnitude. Furthermore, the RSDs of all Cu spectral lines are reduced, especially for Cu I 521.82 nm, which is decreased from 11.48% to 1.36%. This indicates a significant improvement in signal stability. Characterization of the tested samples using con-focal microscopy reveals that the ablation area of MPT-LIBS is only 1.36 times of that of LIBS. The limit of detection of Cu I 324.75 nm line is reduced from 52.8 ppk to 319 ppm.