Anguang Institute of Vacuum UV Photoionization Mass Spectrometry and its application research have made important progress

[ China Instrument Network Instrument Development ] The free radical concentration in the atmosphere, short life and strong chemical activity, as a reaction intermediate in the atmospheric oxidation process often plays a key role. It is of great significance to carry out research on key chemical reactions of free radicals to reveal the oxidative properties of the atmosphere and the causes of pollution. Among them, the comprehensive detection of free radical reaction species (reactants, transient intermediates and reaction products, etc.) and the identification of isomers with different structures have been hot and difficult issues in this research field.

Vacuum ultraviolet photoionization time-of-flight mass spectrometer combined with microwave discharge flow tube device to study atmospheric free radical reaction

(a) High resolution mass spectrum of benzene, toluene and xylene (M/ΔM = 2100); (b) Photoionization mass spectrum of methyl radical (LOD = 3 ppb)

Recently, the research team of An Guangshang Zhang Weijun has made important progress in the research of vacuum ultraviolet photoionization mass spectrometry and the application of free radical reaction kinetics. The related research results are "A vacuum ultraviolet photoionization time-of-flight mass spectrometer with high sensitivity for study". The gas phase radical reaction in flow tube" is published online in the international journal International Journal of Chemical Kinetics (DOI: 10.1002/kin.21241).

The research team Tang Xiaofeng, associate researcher, further developed the vacuum ultraviolet photoionization mass spectrometry technology through the ingenious design of a new iontophoreser. Combined with the self-developed high-resolution, high-sensitivity small-reflection time-of-flight mass spectrometer, not only the free radicals in the flow reaction system were realized. The high-sensitivity mass spectrometry has reached the advanced level among international peers. At the same time, using synchrotron radiation as the ionization source, the full-scale detection of free radical reaction species was realized by vacuum ultraviolet photoionization mass spectrometry, and the photoionization efficiency spectrum was used to distinguish the same efficiently. Isomers.

The editors and reviewers of the International Journal of Chemical Kinetics journals have shown great interest in this research, pointing out that "highly sensitive free radical detection is very beneficial for the study of reaction kinetics in the atmosphere and combustion chemistry" (lowered the limit of detection to about) 0.8 parts per billion, which is much-needed to address low density species such as radicals in chemical kinetics experiments relevant to atmospheric and combustion chemistry), "very good start, expect more interesting work" (this is a new interesting start) /beginning and authors very likely will publish interesting work in future).

The research work was supported by the National Key Research and Development Program, the National Natural Science Foundation and the Chinese Academy of Sciences' International Cooperation Key Project.

(Original title: Anguang's vacuum ultraviolet photoionization mass spectrometry technology and application research has made important progress)