基于激光诱导击穿光谱对钛元素自吸收效应的分析  

Analysis of Titanium Self-absorption Effect Based on Laser-induced Breakdown Spectroscopy

作　　者：童巨红 袁梦甜 王朋 钱龙 田志辉 宣文静 余华清 曾庆栋 TONG Juhong;YUAN Mengtian;WANG Peng;QIAN Long;TIAN Zhihui;XUAN Wenjing;YU Huaqing;ZENG Qingdong(School of Physics and Electronic Information Engineering,Hubei Engineering University,Xiaogan,Hubei 432000,China;College of Physics and Electronic Science,Hubei University,Wuhan,Hubei 430062,China;Department of Information Engineering,College of Technology,Hubei Engineering University,Xiaogan,Hubei 432000,China)

机构地区：[1]湖北工程学院物理与电子信息工程学院,湖北孝感432000 [2]湖北大学物理与电子科学学院,武汉430062 [3]湖北工程学院新技术学院信息工程系,湖北孝感432000

出　　处：《中国无机分析化学》2024年第2期233-238,共6页Chinese Journal of Inorganic Analytical Chemistry

基　　金：国家自然科学基金资助项目(61705064);湖北省自然科学基金资助项目(2021CFB607);孝感市自然科学计划项目(XGKJ 202101003,XGKJ2022010104)。

摘　　要：为了减小谱线自吸收效应对样品物质中元素定量分析带来的干扰,提高激光诱导击穿光谱技术(LIBS)对钢铁中微量元素的检测准确度和精度,以攀钢生铁标准样品作为研究对象,选取Fe(Ⅰ)438.4 nm、Fe(Ⅰ)347.6 nm作为内标线,以原子线Ti(Ⅰ)506.5 nm、离子线Ti(Ⅱ)334.9 nm作为分析线,对Ti元素谱线的自吸收效应进行校正,分别建立内定标曲线,并建立了相应的量化模型。先通过指数函数拟合定标曲线来表征自吸收效应,然后对自吸收效应进行校正。自吸收校正后,Ti两组定标曲线的决定系数R 2分别从0.882增加到0.994、0.881增加到0.917,分别提高了12.7%和4.0%。定量分析时,2#和5#样品用于验证,结果显示两验证样品中Ti预测浓度的相对误差都降低到了10%以内,预测浓度的相对误差分别减少了72.01%、97.10%,测量精度得到明显提高,并且自吸收校正后的预测浓度近似于等于标准浓度。实验表明,通过指数函数拟合定标曲线的方式来量化自吸收效应,并对其进行校正的方法可以提升对Ti的分析精度,方法为通过探索改善自吸收效应来提高LIBS技术的定量分析性能提供了参考依据。In order to reduce the interference caused by the self-absorption effect of spectral lines on the quantitative analysis of elements in sample materials and improve the accuracy and detection of trace elements in steel by laser induced breakdown spectroscopy(LIBS),the Pangang pig iron standard sample was selected as the research object,Fe(Ⅰ)438.4 nm and Fe(Ⅰ)347.6 nm were selected as internal standard line,and atomic line Ti(Ⅰ)506.5 nm and Ti(Ⅱ)334.9 nm were used as analytical lines to correct the self-absorption effect of Ti element spectral lines.Internal calibration curvesand corresponding quantitative models were established.Firstly,the self-absorption effect was characterized by fitting the calibration curve with an exponential function,and then the self-absorption effect was corrected.After self-absorption correction,the determination coefficients R 2 of the two calibration curves for Ti increased from 0.882 and 0.881 to 0.994 and 0.917,respectively,increasing by 12.7%and 4.0%.During the quantitative analysis,samples 2#and 5#were used for validation.The results showed that the relative error of Ti predicted concentration in both validation samples decreased to within 10%,and the relative error of predicted concentration decreased by 72.01%and 97.10%,respectively.The measurement accuracy was significantly improved,and the predicted concentration after self-absorption correction was approximately equal to the standard concentration.Experiments showed that the precision of Ti analysis was improved by fitting the calibration curve with exponential function to quantify the self-absorption effect and calibrate it.This method provides a reference for exploring and improving the quantitative analysis performance of LIBS technology by improving the self-absorption effect.

关 键 词：自吸收效应 定量分析 激光诱导击穿光谱 内定标曲线模型 

分 类 号：O657.38[理学—分析化学] O433.4[理学—化学]