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Controllable Charge Transfer in Ag-TiO? Composite Structure for SERS Application.

ABSTRACT: The nanocaps array of TiO?/Ag bilayer with different Ag thicknesses and co-sputtering TiO?-Ag monolayer with different TiO? contents were fabricated on a two-dimensional colloidal array substrate for the investigation of Surface enhanced Raman scattering (SERS) properties. For the TiO?/Ag bilayer, when the Ag thickness increased, SERS intensity decreased. Meanwhile, a significant enhancement was observed when the sublayer Ag was 10 nm compared to the pure Ag monolayer, which was ascribed to the metal-semiconductor synergistic effect that electromagnetic mechanism (EM) provided by roughness surface and charge-transfer (CT) enhancement mechanism from TiO?-Ag composite components. In comparison to the TiO?/Ag bilayer, the co-sputtered TiO?-Ag monolayer decreased the aggregation of Ag particles and led to the formation of small Ag particles, which showed that TiO? could effectively inhibit the aggregation and growth of Ag nanoparticles.

SUBMITTER: Wang Y

PROVIDER: S-EPMC5535225 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Controllable Charge Transfer in Ag-TiO₂ Composite Structure for SERS Application.

Wang Yaxin Y Yan Chao C Chen Lei L Zhang Yongjun Y Yang Jinghai J

Nanomaterials (Basel, Switzerland) 20170628 7

The nanocaps array of TiO₂/Ag bilayer with different Ag thicknesses and co-sputtering TiO₂-Ag monolayer with different TiO₂ contents were fabricated on a two-dimensional colloidal array substrate for the investigation of Surface enhanced Raman scattering (SERS) properties. For the TiO₂/Ag bilayer, when the Ag thickness increased, SERS intensity decreased. Meanwhile, a significant enhancement was observed when the sublayer Ag was 10 nm compared to the pure Ag monolayer, which was ascribed to the ...[more]

PMID: 28657599

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