title: Ordered arrays of Au-nanobowls loaded with Ag-nanoparticles as effective SERS substrates for rapid detection of PCBs.
abstract: Large-scale hexagonally close-packed arrays of Au-nanobowls (Au-NBs) with tens of Ag-nanoparticles (Ag-NPs) dispersed in each bowl (denoted as Ag-NPs@Au-NB arrays) are achieved and utilized as effective surface-enhanced Raman scattering (SERS) substrates. The field enhancement benefiting from the special particle-in-cavity geometrical structure as well as the high density of SERS hot spots located in the sub-10 nm gaps between adjacent Ag-NPs and at the particle-cavity junctions all together contribute to the high SERS activity of the Ag-NPs@Au-NB arrays; meanwhile the ordered morphological features of the Ag-NPs@Au-NB arrays guarantee uniformity and reproducibility of the SERS signals. By modifying the Ag-NPs@Au-NB arrays with mono-6-thio-β-cyclodextrin, the SERS detection sensitivity to 3,3('),4,4(')-tetrachlorobiphenyl (PCB-77, one congener of polychlorinated biphenyls (PCBs, kinds of persistent organic pollutants which represent a global environmental hazard)) can be further improved and a low concentration down to 5 × 10(-7) M can still be examined, showing promising potential for application in rapid detection of trace-level PCBs in the environment.
authors.affiliation: Key Laboratory of Materials Physics, and Anhui Key Laboratory of Nanomaterials and Nanostructures, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, Anhui 230031, People's Republic of China.
authors.forename: Bensong
authors.initials: B
authors.lastname: Chen
authors.forename: Guowen
authors.initials: G
authors.lastname: Meng
authors.forename: Fei
authors.initials: F
authors.lastname: Zhou
authors.forename: Qing
authors.initials: Q
authors.lastname: Huang
authors.forename: Chuhong
authors.initials: C
authors.lastname: Zhu
authors.forename: Xiaoye
authors.initials: X
authors.lastname: Hu
authors.forename: Mingguang
authors.initials: M
authors.lastname: Kong
mesh_terms: D004785:Environmental Pollutants / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D053758:Nanoparticles; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D015203:Reproducibility of Results; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D047392:beta-Cyclodextrins
chemical_list: D004785:Environmental Pollutants; D047392:beta-Cyclodextrins; D012834:Silver; D006046:Gold; D011078:Polychlorinated Biphenyls; C031215:betadex; C028451:3,4,3',4'-tetrachlorobiphenyl