水溶液中微量Cu元素的激光诱导光谱检测

采用普通打印纸作为基底置于含有痕量重金属离子的水溶液中，用于富集溶液中的重金属Cu元素，烘干后用激光诱导击穿光谱进行定量分析。该方法克服了用激光诱导击穿光谱方法直接分析液相样品中重金属含量时存在水的溅射和灵敏度低等不足。实验中选用324.7 nm的光谱线作为分析线，研究了光谱强度与富集时间的关系，建立了用于溶液中Cu元素定量测量的校正曲线，检测限达到0.023 mg·L-1。为水体中重金属检测提供了一个可行的具有良好灵敏度分析技术。

Determination of Trace Cu in Water by Laser-Induced Breakdown Spectroscopy

In the present article, the ordinary printing paper was immerged in the aqueous solution of CuCl₂, and used as an absorber for the enrichment of heavy metal copper in liquid, After being taken from the solution and dried, the paper was then analyzed using laser-induced breakdown spectroscopy. This method overcomes the drawbacks of splashing and low sensitivity in the process of direct analysis of heavy metal in water sample with LIBS. The Cu 324.7 nm spectral line was used as the analysis line in experiment. The variation in the line intensity at different enrichment time was studied. The calibration curve for the quantitative measurement of Cu in water was established, the detection limit was 0.023 mg·L-1, which is about three orders of magnitude improvement compared with that in ordinary LIBS analysis of heavy metal in solution. It is likely that this technique will be practically helpful in the sensitive analysis of the heavy metal in water.