激光诱导击穿光谱(LIBS)技术已成功地对固体样品和气相样品中的重金属痕量元素进行了定性或半定量分析。为对液体基质的重金属元素进行痕量分析, 使用实验中容易实现的单脉冲激光诱导击穿光谱技术,测定了AlCl3水溶液的激光诱导击穿光谱。系统地研究了溶液中Al原子激光诱导击穿光谱信号的时间演化特性、激光能量对激光诱导击穿光谱信号的影响和激光诱导击穿光谱用于液体中AlCl3痕量分析的检测限。实验结果表明,此方法所适用的激光能量比前人所做实验的激光能量小,只需50 mJ左右,这使得实验条件更容易得到满足,同时得到了一个较高的液体样品的激光诱导击穿光谱信号检测限。实验还表明,液体激光诱导击穿光谱信号存在特有的时间演化特性,其激光诱导击穿光谱信号的寿命相对于固体样品激光诱导击穿光谱信号来说比较短,只有30 ns左右,同时激光诱导击穿光谱信号强度上升和衰减也比较迅速。

The laser-induced breakdown spectroscopy (LIBS) technique has been successfully employed for qualitative and semi-quantitative elemental analysis of trace heavy metal element in solid samples and gas samples. To make an analysis of the heavy metal trace element in liquid, the LIBS of the AlCl3 solution was measured with the single pulse LIBS technique applied flexibly in experiment. The time revolution properties of the Al LIBS signal in the solution, the dependence of the LIBS signal on the laser energy, and the detection limit of the LIBS technique were also investigated. The experimental result showed that the laser energy suitable for this experiment is approximately 50 mJ and lower than that reported in previous experiments. With this easy realizable experiment, a higher detection limit of the LIBS in liquid samples was obtained. The result also showed that there are peculiar time revolution properties of the LIBS signal in liquid. The lifetime of LIBS signal in liquid samples was shorter than that in solid samples, about 30 ns. Meanwhile, the LIBS signal intensity increased and decreased quickly, only lasting several ns.