不同气压下银纳米粒子增强激光诱导等离子体信号
Nanoparticle enhanced laser induced plasma signal technology
刘佳琪 1柯伟 1袁欢 1杨爱军 1王小华 1荣命哲1
作者信息
- 1. 西安交通大学 电气工程学院,陕西 西安 710049
- 折叠
摘要
基于激光诱导击穿光谱技术实现带电检测真空开关真空度亦成为趋势,该技术可以达到10-3 Pa的检测能力.然而,现有激光诱导击穿光谱技术(LIBS)存在检测限较高、灵敏度较低等问题,因此提出一种基于金属纳米粒子的增强技术来提高真空开关真空度带电检测精度.通过在样品表面涂覆银纳米粒子层,降低激光击穿阈值,提升信号谱线强度.研究了不同气压下激光诱导等离子体信号随延迟时间以及试剂浓度的变化规律,研究结果表明,银纳米粒子在常气压下对信号增强可达1～2 个数量级,且浓度越高,增强效果越好.在低气压下,银纳米粒子的信号增强达到1～2 倍,随着气压降低,增强倍数先增大后减小,且等离子体被激发时间早于大气压下.银纳米粒子对背景噪声辐射强度没有显著影响,因此使用银纳米粒子可以有效提高等离子体信号的信噪比,对真空开关真空度带电检测起到一定优化作用.
Abstract
It has also become a trend to realize charged detection of vacuum switch vacuum based on la-ser-induced breakdown spectroscopy,which can achieve a detection capability of 10-3 Pa.However,in the laser-induced breakdown spectroscopy(LIBS)technique there exist problems such as high detection limit and low sensitivity,so an enhancement technique was proposed based on metal nanoparticles to im-prove the precision of charged detection of vacuum switch vacuum.By coating a silver nanoparticle layer on the sample surface,the laser breakdown threshold is lowered and the signal spectral line intensity is enhanced.The variation rule of laser-induced plasma signal with delay time and reagent concentration un-der different air pressure was investigated,and the results show that silver nanoparticles can enhance the signal up to 1-2 orders of magnitude under normal air pressure,and the higher the concentration,the better the enhancement effect.Under low air pressure,the signal enhancement of silver nanoparticles rea-ches 1-2 times,and as the air pressure decreases,the enhancement times first increase and then de-crease,and the plasma is excited earlier than under atmospheric pressure.Silver nanoparticles have no significant effect on the background noise radiation intensity,so the use of silver nanoparticles can effec-tively improve the signal-to-noise ratio of the plasma signal,and play a certain optimization role in the vacuum switch vacuum charged detection.
关键词
激光诱导等离子体/真空度/激光诱导击穿光谱技术/纳米粒子增强/带电检测/等离子体Key words
laser induced plasma/vacuum degree/laser induced breakdown spectroscopy/nanoparticle-enhanced laser-induced breakdown spectroscopy/on-line monitoring/plasma引用本文复制引用
基金项目
国家自然科学基金(51777154)
中国博士后科学基金(2020M683481)
出版年
2024
NETL
NSTL
维普
万方数据