Heterogeneous Reactions on the Surface of Atmospheric Particles：A Transmission FTIR Spectroscopy Study
JIE Chong-yu,CHEN Zhong-ming*,LI Shuang,WANG Hong-li
The State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Science, Peking University, Beijing 100871, China
Abstract：Heterogeneous reactions of trace gases on the surface of particles in the atmosphere play a important role in the key atmospheric processes, and have been of increasingly interest in atmospheric sciences.However, these reactions, especially the corresponding detailed kinetics and mechanisms, have not been well understood, due to the deficiencies in the current experimental methods.The authors developed a novel experimental method for the study of heterogeneous reactions, based on transmission FTIR spectroscopy (T-FTIR), providing an understanding of the detailed physical chemistry that occurs on the surface of particles at the molecular level.In this method, the particles were evenly coated on a metal grid, and the gaseous reactant and the infrared beam were introduced to pass through the grid in the reactor.This method was used to explore the heterogeneous reaction of methacrolein (MAC) on the surface of SiO2 particles, a model heterogeneous reaction, under simulated atmospheric conditions.The result demonstrated that T-FTIR is an applicable and powerful technique for the qualitative and quantitative analysis of such a heterogeneous reaction, due to its excellent spectral signal.In addition, the particle sample will not be scathed due to the low energy of infrared light, thus the in situ investigation of the reaction on particles could be carried out.Compared with the HPLC analysis results, the repeatability and accuracy of the qualitative and quantitative analysis of T-FTIR have proven satisfactory, even though the reactions ran in the humid air.The authors’ method can provide an effective tool for the laboratory simulation of heterogeneous reactions under the atmospheric conditions.
[1] Hastings W P, Koehler C A, Bailey E L, et al.Environ.Sci.Technol, 2005, 39(22)：8728. [2] Liggio J, Li S M, Brook J R, et al.Geophys.Res.Lett., 2007, 34(5)：L05814. [3] Li P, Perreau K A, Covington E, et al.J.Geophys.Res., 2001, 106(6)：5517. [4] Carlos-Cuellar S, Li P, Christensen A P, et al.J.Phys.Chem.A, 2003, 107(21)：4250. [5] Brensen C, Kirchner U, Scheer V, et al.J.Phys.Chem.A, 2000, 104：5036. [6] Ullerstam M, Vogt R, Langer S, et al.Phys.Chem.Chem.Phys., 2002, 4：4694. [7] LI Lei, CHEN Zhong-ming, DING Jie, et al(李 雷，陈忠明，丁 杰，等).Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2004, 24(12)：1556. [8] ZHANG Yun-hong, HU Yong-an, DING Fei, et al.Chinese Science Bulletin, 2005, 50(19)：2149. [9] Dubowski Y, Vieceli J, Tobias D J.J.Phys.Chem.A, 2004, 108：10473. [10] XU Yi-kun, ZHAN Mao-sheng(徐一琨，詹茂盛).Journal of Aeronautical Materials(航空材料学报), 2003, 23(2)：33. [11] Grosjean D, William Ⅱ E L, Grosjean E.Environ.Sci.Technol, 1993, 27：830. [12] CHEN Zhong-ming, LI Shuang, SHI Fei, et al(陈忠明，李 爽，史 飞，等).Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2003, 23(4)：742. [13] WANG Cai-xia, CHEN Zhong-ming, XU Jin-rong(王彩霞，陈忠明，徐金荣).Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2006, 26(12)：2222. [14] WEI Xiu-li, LU Yi-huai, GAO Min-guang, et al(魏秀丽，陆亦怀，高闽光，等).Spectroscopy and Spectral Analysis(光谱学与光谱分析), 2007, 27(4)：668. [15] Grassian V H.International Review of Physical Chemistry, 2001, 20(3)：467. [16] JIE Chong-yu, CHEN Zhong-ming, WANG Hong-li, et al.Chinese Science Bulletin, 2008，53(7)：1004.
