title: Silver nanoparticles decorated nanoporous gold for surface-enhanced Raman scattering.
abstract: Raman spectra are considered as signatures of matter and have been widely used to identify several classes of materials. The development of mobile spectrometers further extends applications of Raman spectroscopy, and both indoor/outdoor and in vivo/in vitro measurements have been evaluated on site. However, the finite detection level restricts its application in high density matters. Here we report a facile silver nanoparticle decorated nanoporous gold (NanoAg@NPG) substrate, which can provide high enhancement of the Raman signal from nearby molecules by 785 nm photoexcitation. This enhancement is attributed to the abundant Raman-active nanogaps constructed by adjacent nanoparticles and also by the NPG ligaments and adhered nanoparticles. This NanoAg@NPG substrate shows great potential as a reproducible and quantifiable near infrared surface-enhanced Raman scattering probe for various targets, since it performs well in the so-called biological window which can avoid autofluorescence and absorption either from targets or surroundings in the visible optical region.
authors.affiliation: Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System (Ministry of Education), School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, People's Republic of China.
authors.forename: Min
authors.initials: M
authors.lastname: Yang
authors.forename: Ling
authors.initials: L
authors.lastname: Zhang
authors.forename: Bin
authors.initials: B
authors.lastname: Chen
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.forename: Chao
authors.initials: C
authors.lastname: Chen
authors.forename: Heping
authors.initials: H
authors.lastname: Zeng