1. 重庆大学三峡库区生态环境教育部重点实验室,重庆 400030 2. 西南大学化学化工学院,重庆 400715 3. Juelich Research Center, Juelich, Germany 52425
The Study of Dimethoate by Means of Vibrational and Surface Enhanced Raman Spectroscopy on Au/Ag Core-Shell Nanoparticles
HE Qiang1, LI Si1, YU Dan-ni2, ZHOU Gunag-ming2, JI Fang-ying1*, Guenter Subklew3
1. Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400030, China 2. School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China 3. Juelich Research Center, Juelich, Germany 52425
Abstract:The vibrational structure of dimethoate, with its solid state and saturated solutions at acidic and basic conditions, was characterized with combination of means of FTIR and FT-Raman vibrational spectroscopy technology, and the comprehensive information about the dimethoate molecular groups’ vibrational features was obtained. The surface enhanced Raman scattering (SERS) spectra of dimethoate at different concentrations with different acidic and basic conditions, and adsorbed on the substrate’s surface of the core-shell Au/Ag nanoparticles, were also obtained. The adsorption states of dimethoate’s molecule on the substrate’s surface of the core-shell Au/Ag nanoparticles and the effects by the different acid-base conditions were investigated, with speculation of the adsorption mechanism. From the results, νas(NH), νas(CH3), ν(OCN), τ(OCN), ν(P—O), ν(PS), ν(C—C) and δ(P—O—C) are the characteristic peaks of inner dimethoate structure’s vibrations; and the concentration range in which dimethoate could interact with core-shell Au/Ag nanoparticles fully is about 1.0×10-3 mol·L-1 both in acidic and basic conditions. Dimethoate’s molecule interacts with SERS’ substrate surface mainly through P—O—C, OCC, (S—CH2), PS, and CH3 structures; and the effects of dimethoate’s hydrolysis path in acidic and basic conditions on the adsorption are discussed, which give some good references for the research of organophosphorus pesticides’ transformations in different environmental systems.
Key words:Dimethoate;Vibrational spectroscopy;SERS;Interaction model
何 强1, 黎 司1, 虞丹尼2, 周光明2, 吉芳英1*, Guenter Subklew3 . 乐果的振动光谱及其在金/银核-壳复合粒子表面的SERS研究 [J]. 光谱学与光谱分析, 2010, 30(12): 3249-3253.
HE Qiang1, LI Si1, YU Dan-ni2, ZHOU Gunag-ming2, JI Fang-ying1*, Guenter Subklew3 . The Study of Dimethoate by Means of Vibrational and Surface Enhanced Raman Spectroscopy on Au/Ag Core-Shell Nanoparticles . SPECTROSCOPY AND SPECTRAL ANALYSIS, 2010, 30(12): 3249-3253.