VUV photoionization aerosol mass spectrometric study on the iodine oxide particles formed from O-3-initiated photooxidation of diiodomethane (CH2I2)
VUV photoionization aerosol mass spectrometric study on the iodine oxide particles formed from O-3-initiated photooxidation of diiodomethane (CH2I2)
复制标题
O3 引发二碘甲烷 (CH2I2) 光氧化形成的氧化碘颗粒的 VUV 光电离气溶胶质谱研究
DOI：
10.1039/c7ra11413c
复制
发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
Sheng Liusi
中科院分区：
文献类型：
--
作者：
Wei Nana;Hu Changjin;Zhou Shanshan;Ma Qiao;Mikuska Pavel;Vecera Zbynek;Gai Yanbo;Lin Xiaoxiao;Gu Xuejun;Zhao Weixiong;Fang Bo;Zhang Weijun;Chen Jun;Liu Fuyi;Shan Xiaobin;Sheng Liusi
首次将热脱附/可调谐真空紫外飞行时间光电离气溶胶质谱仪（TD-VUV-TOF-PIAMS）与流动反应器相结合，研究了O3引发二碘甲烷光氧化生成的氧化碘粒子（IOPs）。对自制的流动反应器进行了表征，表明了其与TD-VUV-TOF-PIAMS联用的适用性。在此基础上，充分利用流动反应器和TD-VUV-TOF-PIMS的优点，对CH_2I_2/O_3光氧化生成IOP的气溶胶质谱进行了在线研究。根据光电离能（PIE）曲线，观察并鉴定了碘化产物的主要化学成分，包括原子和分子碘（I，I2）、碘氧化物（IO，OIO，I2 O和I2 O3）和含氢碘物种（HI，HIO和HIO 3），并提出了碘化产物可能的化学组成和形成机理。该工作不仅提高了对IOPs形成机理的认识，而且证明了TD-VUV-TOF-PIAMS在流动反应器实验中直接表征气溶胶分子的能力，预计其在大气气溶胶质谱研究中的潜在应用。
Iodine oxide particles (IOPs) formed from O3-initiated photooxidation of diiodomethane have been investigated based on the combination of a thermal desorption/tunable vacuum ultraviolet time-of-flight photoionization aerosol mass spectrometer (TD-VUV-TOF-PIAMS) with a flow reactor for the first time. Characterization of the home-made flow reactor was performed, which indicates the applicability of its combination with TD-VUV-TOF-PIAMS. Based on that, aerosol mass spectra of IOP formation from photooxidation of CH2I2/O3 were studied on-line taking full advantage of both the virtues of the flow reactor and TD-VUV-TOF-PIAMS. The main chemical components of IOPs, including atomic and molecular iodine (I, I2), iodine oxides (IO, OIO, I2O and I2O3) and hydrogen-containing iodine species (HI, HIO and HIO3), were observed and identified based on the corresponding photoionization energy (PIE) curves, and the probable chemical composition and formation mechanism of IOPs were proposed. The work has not only improved the understanding of the formation mechanism of IOPs, but also demonstrated the capability of TD-VUV-TOF-PIAMS for direct molecular characterization of aerosols in flow reactor experiments, whose potential application in mass spectrometric studies of atmospheric aerosols is anticipated.