Quasi-Trapping Chemical Ionization Source Based on a Commercial VUV Lamp for Time-of-Flight Mass Spectrometry

详细信息    查看全文

• 作者：Ping Chen ; Keyong Hou ; Lei Hua ; Yuanyuan Xie ; Wuduo Zhao ; Wendong Chen ; Chuang Chen ; Haiyang Li
• 刊名：Analytical Chemistry
• 出版年：2014
• 出版时间：February 4, 2014
• 年：2014
• 卷：86
• 期：3
• 页码：1332-1336
• 全文大小：280K
• ISSN：1520-6882

文摘

The application of VUV lamp-based single photon ionization (SPI) was limited due to low photon energy and poor photon flux density. In this work, we designed a quasi-trapping chemical ionization (QT-CI) source with a commercial VUV 10.6 eV krypton lamp for time-of-flight mass spectrometry. The three electrode configuration ion source with RF voltage on the second electrode constitutes a quasi-trapping region, which has two features: accelerating the photoelectrons originated from the photoelectric effect with VUV light to trigger the chemical ionization through ion鈥搈olecule reaction and increasing the collisions between reactant ion O₂⁺ and analyte molecules to enhance the efficiency of chemical ionization. Compared to single SPI based on VUV krypton lamp, the QT-CI ion source not only apparently improved the sensitivity (e.g., 12鈥?18 fold enhancement were achieved for 13 molecules, including aromatic hydrocarbon, chlorinated hydrocarbon, hydrogen sulfide, etc.) but also extended the range of ionizable molecules with ionization potential (IP) higher than 10.6 eV, such as propane, dichloroethane, and trichloromethane.