In Situ Creation of Surface-Enhanced Raman Scattering Active Au–AuOx Nanostructures through Electrochemical Process for Pigment Detection
journal contributionposted on 05.12.2018, 09:14 by Hsiao-Chien Chen, Ching-Hsiang Chen, Chia-Shuo Hsu, Tai-Lung Chen, Mei-Yi Liao, Chia-Ching Wang, Chia-Fen Tsai, Hao Ming Chen
Roughing the metallic surface via oxidation–reduction cycles (ORC) to integrate the surface plasmon resonance and surface-enhanced Raman scattering (SERS) is predominant in developing sensor systems because of the facile preparation and uniform distribution of nanostructures. Herein, we proposed a distinctive ORC process: the forward potential passed through the oxidation of Au and reached the oxygen evolution reaction, and once the potential briefly remained at the vertex, the various reverse rates were employed to control the reduction state. The created hybrid Au–AuOx possessed electromagnetic and chemical enhancements concurrently, wherein the rough surface provided the strong local electromagnetic fields and significant interaction between AuOx and molecule to improve the charge transfer. The synergistic effects significantly amplified the intensity of Raman signal with an enhancement factor of 5.5 × 106 under the optimal conditions. Furthermore, the prepared SERS substrate can simultaneously identify and quantify the mixed edible pigments, Brilliant Blue FCF and Indigo Carmine, individually. This result suggested that the development of SERS sensor based on the proposed SERS-activated methodology is feasible and reliable.
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AuO xchemical enhancementsBrilliant Blue FCFSERS-activated methodologyORC processSitu Creationcharge transferenhancement factorsensor systemsoxidationRaman signaloxygen evolution reactionPigment Detection RoughingSurface-Enhanced Raman ScatteringSERS substratereduction stateelectromagnetic fieldssurface plasmon resonancesurface-enhanced Ramanuniform distributionIndigo CarmineSERS sensorElectrochemical Process