title: Fabrication of thorny Au nanostructures on polyaniline surfaces for sensitive surface-enhanced Raman spectroscopy.
abstract: Here we demonstrate, for the first time, the fabrication of Au nanostructures on polyaniline (PANI) membrane surfaces for surface enhanced Raman spectroscopy (SERS) applications, through a direct chemical reduction by PANI. Introduction of acids into the HAuCl(4) solution leads to homogeneous Au structures on the PANI surfaces, which show only sub-ppm detection levels toward the target analyte, 4-mercaptobenzoic acid (4-MBA), because of limited surface area and lack of surface roughness. Thorny Au nanostructures can be obtained through controlled reaction conditions and the addition of a capping agent poly (vinyl pyrrolidone) (PVP) in the HAuCl(4) solution and the temperature kept at 80 °C in an oven. Those thorny Au nanostructures, with higher surface areas and unique geometric feature, show a SERS detection sensitivity of 1 × 10(-9) M (sub-ppb level) toward two different analyte molecules, 4-MBA and Rhodamine B, demonstrating their generality for SERS applications. These highly sensitive SERS-active substrates offer novel robust structures for trace detection of chemical and biological analytes.
authors.affiliation: Department of Chemistry, Harbin Institute of Technology, Harbin 150001, China.
authors.forename: Siwei
authors.initials: S
authors.lastname: Li
authors.forename: Ping
authors.initials: P
authors.lastname: Xu
authors.forename: Ziqiu
authors.initials: Z
authors.lastname: Ren
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Yunchen
authors.initials: Y
authors.lastname: Du
authors.forename: Xijiang
authors.initials: X
authors.lastname: Han
authors.forename: Nathan H
authors.initials: NH
authors.lastname: Mack
authors.forename: Hsing-Lin
authors.initials: HL
authors.lastname: Wang
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry*; D001565:Benzoates / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D011205:Povidone / Q000737:chemistry; D012235:Rhodamines / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013438:Sulfhydryl Compounds / Q000737:chemistry
chemical_list: D000814:Aniline Compounds; D001565:Benzoates; D012235:Rhodamines; D013438:Sulfhydryl Compounds; C416807:polyaniline; C013594:4-mercaptobenzoate; D006046:Gold; D011205:Povidone; C029773:rhodamine B