Quasi-metallic Tungsten Oxide Nanodendrites with High Stability for Surface-Enhanced Raman Scattering

• Main Authors: Yuting Ye, Chao Chen, Hua Bai, Wei Liu, Wentao Li, Junfang Li, Wencai Yi, Guangcheng Xi
• Format: Article
• Language: English
• Published: Elsevier 2020-03-01
• Series: Cell Reports Physical Science
• Subjects: quasi-metallic WO2; scale-up synthesis; SERS; single-molecule detection; interface charge transfer; surface plasma resonance
• Online Access: http://www.sciencedirect.com/science/article/pii/S2666386420300217

Summary: As a non-destructive and label-free detection technology, surface-enhanced Raman scattering (SERS) has been widely used in environmental-pollutant detection, biological-tissue sensing, molecular fingerprint analysis, and so on. Herein, we report an active SERS material, namely quasi-metallic WO2 nanodendrites. Due to the dual boosts of electromagnetic mechanism (EM) enhancement and chemical mechanism (CM) enhancement, the WO2 nanodendrites achieve an 8.5 × 107 level enhanced factor and a 10−10 level detection limit for probe molecules. The experimental and theoretical results demonstrate that the performance comes from the dual enhancement of the highly efficient interface charge transfer and the vigorous surface plasma resonance (SPR) of the quasi-metals. Furthermore, these WO2 nanodendrites show high chemical stability, are resistant to long-term air oxidation, and even can endure strong acid and alkali corrosion without reducing their SERS activity. The separation and detection of multicomponent samples are achieved simultaneously when these nanodendrites are fabricated into patterned SERS chips.