基于大气压下介质阻挡放电抑制LA-ICP-MS分析中元素分馏效应研究  

New Strategy Based on Dielectric Barrier Discharge Under Atmospheric Pressure to Inhibit Elemental Fractionation Effect in LA-ICP-MS

作　　者：张路远[1] 胡圣虹[1] 胡兆初[2] 胡明月[3] 郭伟[1] 刘勇胜[2] 

机构地区：[1]中国地质大学(武汉)生物地质与环境地质教育部重点实验室,武汉430074 [2]中国地质大学(武汉)地质过程与矿产资源国家重点实验室,武汉430074 [3]国家地质实验测试中心,北京100037

出　　处：《高等学校化学学报》2008年第10期1947-1952,共6页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20575061);教育部科学技术重点项目资金(批准号:108090)资助

摘　　要：采用自制的大气压下介质阻挡放电装置串联在激光剥蚀池与ICP炬管之间,对激光剥蚀产生的气溶胶进行预电离.结果表明,元素瞬时信号轮廓的平滑度得以改善,元素分析信号精密度(RSD,n=3)可提高2.55%.在ArF准分子激光(193 nm)和Nd∶YAG固体激光(213 nm)两种不同波长的激光剥蚀系统中,元素分馏因子均比常规模式下更接近于1,表明采用介质阻挡放电对气溶胶预电离后元素分馏效应得以有效抑制.相比两种不同波长的激光剥蚀系统,介质阻挡放电对213 nm固体激光的元素分馏效应改善作用明显.A new strategy based on a house-made dielectric barrier discharge （DBD） device to inhibit elemental fractionation effect was developed. The DBD device was connected in between laser ablation cell and ICP torch. The aerosols induced by laser ablation were preionized in the DBD and the particle sizes of aerosol were decreased. The results indicate that elemental time-resolved signals are less fluctuant in DBD mode than normal mode during the laser ablation processes. In the ArF excimer 193 nm LA-ICP-MS, the average precision of signal intensities （ RSD, n = 3 ） with DBD mode and normal mode was 1.46% and 4.01%, respectively, and the signal intensities were reduced within 15%. While the average precision and signal intensities were found no significant change in presence and in absence of the DBD device for the 213 nm LA-ICP-MS. No obvious change was obtained for the elemental fractionation index in the 193 nm laser ablation system with the DBD device. The elemental fractionation index was closer to 1 with the DBD for 213 nm LA-ICP-MS. The results demonstrate the elemental fractionation effect was inhibited availably with the DBD device.

关 键 词：LA-ICP-MS 元素分馏效应 介质阻挡放电 

分 类 号：O657.63[理学—分析化学]