A research on the effect of plasma spectrum collection device on LIBS spectral intensity  

作　　者：林晓梅 董艳杰 林京君 黄玉涛 杨江飞 岳星宇 张倬嘉 段鑫杨 Xiaomei LIN;Yanjie DONG;Jingjun LIN;Yutao HUANG;Jiangfei YANG;Xingyu YUE;Zhuojia ZHANG;Xinyang DUAN(Changchun University of Technology,Changchun130012,People’s Republic of China)

机构地区：[1]Changchun University of Technology,Changchun130012,People’s Republic of China

出　　处：《Plasma Science and Technology》2024年第5期121-128,共8页等离子体科学和技术（英文版）

基　　金：supported by Department of Science and Technology of Jilin Province of China(Nos.YDZJ202301 ZYTS481,202202901032GX,and 20230402068GH)。

摘　　要：Only a small amount of spectral information is collected because the collection solid angle of the optical fiber probe and lens is very limited when collecting spectral information.To overcome this limitation,this study presents a novel method for acquiring plasma spectral information from various spatial directions.A parabolic-shaped plasma spectral collection device(PSCD)is employed to effectively collect more spectral information into the spectrometer,thereby enhancing the overall spectral intensity.The research objects in this study were soil samples containing different concentrations of heavy metals Pb,Cr,and Cd.The results indicate that the PSCD significantly enhances the spectral signal,with an enhancement rate of up to 45%.Moreover,the signal-to-noise ratio also increases by as much as 36%.Simultaneously,when compared to the absence of a device,it is found that there is no significant variation in plasma temperature when the PSCD is utilized.This observation eliminates the impact of the spatial effect caused by the PSCD on the spectral intensity.Consequently,a concentrationspectral intensity relationship curve is established under the PSCD.The results revealed that the linear fitting R^(2)for Pb,Cr,and Cd increased by 0.011,0.001,and 0.054,respectively.Additionally,the limit of detection(LOD)decreased by 0.361 ppm,0.901 ppm,and 0.602 ppm,respectively.These findings indicate that the spectral enhancement rate elevates with the increase in heavy metal concentration.Hence,the PSCD can effectively enhance the spectral intensity and reduce the detection limit of heavy metals in soil.

关 键 词：LIBS plasma spectrum collection device spectral enhancement plasma temperature limit of detection 

分 类 号：O657.38[理学—分析化学]