|
|
|
|
|
|
| Simulation and Optimization Design of ICP-MS Off-Axis Transmission Lens |
| LI Kai1, 2, WANG Lei1, 2, WANG Hai-zhou1, 2*, WANG Li-ping2, FANG Zhe1, 2, WANG Chao-gang2, PAN Gao-yang2 |
1. Central Iron and Steel Research Institute Co., Ltd., Beijing 100081, China
2. NCS Testing Technology Co., Ltd., Beijing 100081, China
|
|
|
|
|
Abstract Inductively coupled plasma mass spectrometer (ICP-MS) is one of the most powerful analytical methods for trace elements due to its high sensitivity and low detection limit. In the design of ICP-MS instruments, effectively introducing the ion beam of the analyte into the post-mass analyzer system is a major challenge. To achieve efficient transmission of ion beams, the ion beam should have a small angle divergence and energy divergence after entering the deflection lens, and be emitted as parallel as possible. That is, the velocity in the vertical direction should be as low as possible. At the same time, to remove neutral particles and photons to the maximum extent and reduce background noise, the vertical deflection displacement should be made larger. This paper draws on the theory of electrostatic fields in electron optics, starting from the motion process of ions in an electrostatic field, and theoretically derives and establishes a model for the motion process of ions in a polarized suspended off-axis deflection lens. Then, using SIMION software, the motion of Li, In, and U ion beams representing low, medium, and high mass numbers in this deflection lens system is simulated and analyzed. The key electric field parameters acceleration voltage Ua, deflection voltage U1, deflection voltage U2, and mechanical parameter L2 in theoretical analysis are examined for their effects on ion beam transmission, including ion deflection displacement sy, vertical velocity v′y at the exit hole, and ion pass rate. Combined with simulation results and design, the effects are investigated. Based on the simulation results and design requirements, this article presents the key parameter values and size optimization design scheme for the off-axis deflection lens. According to the optimized design scheme provided by software simulation, three sizes of deflection lens systems were applied to ICP-MS instruments for comparative testing of background noise and sensitivity to verify the reliability of the simulation. The experimental results showed that the background noise and sensitivity were significantly improved with the optimized structure, especially for low-mass numbers. The background noise was reduced by about 2 times and the sensitivity was increased by about 4 times. Although there may be some errors between simulation and actual results, the overall trend is correct. It can guide the structural design and electrical parameter optimization of deflection lens systems in practice.
|
|
Received: 2024-03-13
Accepted: 2024-07-30
|
|
|
|
Corresponding Authors:
WANG Hai-zhou
E-mail: wanghaizhou@ncschina.com
|
|
[1] Smoluch M, Grasso G, Suder P. Massspectrometry: An Applied Approach. New Jersey: John Wiley & Sons, Inc., 2019.
[2] Tetsumasa I, Yoshitomo N. Plasma Ion Source Mass Analyzing Apparatus: United States, 5559337. 1996.
[3] Iouri K. Ion Optical System for a Mass Spectrometer: United States, 6614021. 2003.
[4] Iouri K. Mass Spectrometry: United States, 9048078. 2015.
[5] DU Bing-chu, WANG Jian-ru(杜秉初，汪健如). Electron Optics(电子光学). Beijing: Tsinghua Unversity Press(北京：清华大学出版社)，2002.
[6] Scott D, Vladimir I. Atomic Spectroscopy，1999，20(2): 45.
[7] Li Xingyu, Guan Lulu, Gao Jiuru, et al. Journal of Manufacturing Processes, 2023, 102: 839.
[8] Vallant B, Kadnar R, Goessler W. J. Anal. At. Spectrom., 2007, 22: 322.
[9] Vadakedath S, Kandi V, GodishalaV, et al. Biomedicine and Biotechnology, 2022, 7(1): 6.
[10] HE Fei-yao, DAI Jian-xiong, FU Yu, et al(贺飞耀, 代渐雄, 付 玉，等). Journal of Chinese Mass Spectrometry Society(质谱学报), 2022, 43(1): 25.
[11] Graczyk D, Mclain D, Tsai Y, et al. Atomic Spectroscopy, 2019, 153: 10.
|
| [1] |
ZHAO Qian-qian1, YAN Lai-lai1,2, XIE Qing1,2, LIU Ya-qiong1,2, YANG Si-yu1, GUO Chen1, WANG Jing-yu1,2*. Effect of Zinc on the Growth and Element Content of Lactobacillus Acidophilus[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2020, 40(05): 1489-1494. |
| [2] |
XU Juan1*, YANG Shou-ye1, HU Zhao-chu2, LUO Tao2, HUANG Xiang-tong1 . A New Sample Fusion Technique for Quantitative Analysis of Major and Minor Elements in Sulfides with X-Ray Fluorescence Spectrometry and Laser Ablation Inductively Coupled Plasma Mass Spectrometry[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2016, 36(11): 3683-3688. |
| [3] |
ZOU Xiao-wen1, 2, GAO Bo1, 2*, ZHOU Huai-dong1, 2, HAO Hong2, XU Dong-yu2 . Determination of Platinum Group Elements in City Roadside Dusts by ICP-MS [J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2016, 36(04): 1202-1204. |
| [4] |
WU Zhao-bin1, 3, CHEN Fang1, 2, 3, CHEN Lan-zhen1, 2, 3*, ZHAO Jing1, 3*, LI Yi1, 2, 3, WU Li-ming1, 2, 3，YE Zhi-hua4 . Application of Inductively Coupled Plasma Mass Spectrometry with Chemometric Methods in Classification of Honeys According to Their Types[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2015, 35(01): 217-222. |
| [5] |
ZHANG Yong1, JIA Yun-hai1*, CHEN Ji-wen1, SHEN Xue-jing1, LIU Ying2, ZHAO Lei2, LI Dong-ling1, HANG Peng-cheng3, ZHAO Zhen3, FAN Wan-lun4, WANG Hai-zhou1. Progress in the Application of Laser Ablation ICP-MS to Surface Microanalysis in Material Science[J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2014, 34(08): 2238-2243. |
| [6] |
WANG Xiao-ping1,ZHANG Ji-long2. Determination of 235U/238U Isotope Ratios in Camphor Tree Bark Samples by MC-ICP-MS after Separation of Uranium from Matrix Elements [J]. SPECTROSCOPY AND SPECTRAL ANALYSIS, 2007, 27(07): 1428-1432. |
|
|
|
|
