LIBS技术对水溶液中Mn、Cd和Cu元素的定量分析研究
Quantitative Analysis of Mn, Cd and Cu Elements in Aqueous Solution Based on LIBS Technology

为了提高激光诱导击穿光谱技术(LIBS)用于水溶液中重金属检测的灵敏度和精确度，采用液体射流的方式，利用不同的定量分析方法对不同浓度的水中重金属(Mn、Cd和Cu)进行了检测和分析。液体射流的方式能够使采集到的光谱更加的稳定，通过使用内标法和外标法进行取点，使用最小二乘拟合进行线性拟合得到定标曲线，计算并比较两种定量方法的精确度，得到Mn、Cd和Cu元素定量分析时内标法的LOD值、相关系数R²和RSD值都要优于外标法。这表明LIBS技术对水溶液中Mn、Cd和Cu元素进行定量分析检测时使用内标法能够获得更好的检测精确度。
In order to improve the sensitivity and accuracy of laser-induced breakdown spectroscopy (LIBS) for the detection of heavy metals in aqueous solutions, different quantitative analysis methods were used to detect and analyze heavy metals (Mn, Cd and Cu) in water with different concentrations by means of liquid jet. The liquid jet method can make the collected spectrum more stable. By using the internal standard method and the external standard method to take points, and using a least square fit to perform a linear fit to obtain a calibration curve, the accuracy of the two quantitative methods is calculated and compared. It is concluded that the LOD value, correlation coefficient R² and RSD value of the internal standard method are superior to those of the external standard method when the Mn, Cd and Cu elements are quantitatively analyzed. Then the speed of quantitative analysis was improved through software integration, and the purpose of rapid quan-titative analysis of heavy metal elements in water was achieved.