title: Cetylpyridinium chloride activated trinitrotoluene explosive lights up robust and ultrahigh surface-enhanced resonance Raman scattering in a silver sol.
abstract: Surface-enhanced resonance Raman scattering (SERRS) is not realized for most molecules of interest. Here, we developed a new SERRS platform for the fast and sensitive detection of 2,4,6-trinitrotoluene (TNT), a molecule with low Raman cross section. A cationic surfactant, cetylpyridinium chloride (CPC) was modified on the surface of silver sols (CP-capped Ag). CPC not only acts as the surface-seeking species to trap sulfite-sulfonated TNT, but also undergoes complexation with it, resulting in the presence of two charge-transfer bands at 467 and 530 nm, respectively. This chromophore absorbs the visible light that matches with the incident laser and plasmon resonance of Ag sols by the use of a 532.06 nm laser, and offered large resonance Raman enhancement. This SERRS platform evidenced a fast and accurate detection of TNT with a detection limit of 5×10(-11) M under a low laser power (200 μW) and a short integration time (3 s). The CP-capped Ag also provides remarkable sensitivity and reliable repeatability. This study provides a facile and reliable method for TNT detection and a viable idea for the SERS detection of various non-resonant molecules.
authors.affiliation: Institute of Intelligent Machines, Chinese Academy of Sciences, Hefei 230031, P.R. China. hlliu@iim.ac.cn
authors.forename: Honglin
authors.initials: H
authors.lastname: Liu
authors.forename: Dongyue
authors.initials: D
authors.lastname: Lin
authors.forename: Yudie
authors.initials: Y
authors.lastname: Sun
authors.forename: Liangbao
authors.initials: L
authors.lastname: Yang
authors.forename: Jinhuai
authors.initials: J
authors.lastname: Liu