水中痕量重金属激光诱导击穿光谱高灵敏检测  

High Sensitive Detection of Trace Heavy Metals in Water by Laser-induced Breakdown Spectroscopy

作　　者：赵芳[1] 张谦[1] 熊威[1] 容静宝[1] 李润华[1] 

机构地区：[1]华南理工大学理学院物理系,广东广州510640

出　　处：《环境科学与技术》2010年第3期137-140,共4页Environmental Science & Technology

基　　金：国家自然科学基金(10874047);华南理工大学SRP课题资助(x2lx-Y1080360)

摘　　要：采用旋转电极,用电沉积的方法把天然水中痕量的有害重金属离子富集到一个高纯(纯度为99.999%)铝棒表面,然后利用激光诱导击穿光谱对其进行定量分析。采用旋转电极能够较好地排除电解水所产生的气泡对重金属离子电沉积过程的干扰。实验研究了铅和镉两种元素,在富集电压为7.5V,富集时间为20min的条件下制定了两个元素的校正曲线并得出其检出限为500ng/L(Pb)和830ng/L(Cd)。该方法为水环境重金属污染监测提供了一种新的分析技术,它具有灵敏度高和可以多元素同时分析两个突出的优点。Trace toxic heavy metal ions in natural water were electrically deposited on the surface of an aluminum rod with 99.999% purity and then quantitatively analyzed by laser-induced breakdown spectroscopy （LIBS）. The interference of gas bubbles generated in the process of electrolysis to electrical-deposition of heavy metal ions was effectively reduced by utilizing a rotating cathode. Pb and Cd were analyzed in experiments and calibration curves of them were established under the condition of 7.5V of deposition voltage and 20min of deposition time. Limits of detection achieved were 500ng/L for Pb and 830ng/L for Cd. The method can provide a new analytical technique for monitoring heavy metal pollutions of water with high detection sensitivity and possibility of multi-elements simultaneous analysis.

关 键 词：激光诱导击穿光谱 电沉积 水环境重金属污染监测 

分 类 号：X830.2[环境科学与工程—环境工程]