Developing highly reliable Ag@NaYF₄ hybrid structures for efficiently improving optical property

Here, we report a rational method for constructing a composite functional surface-enhanced Raman scattering (SERS) substrate, which is prepared by modifying the surfaces of β-NaYF₄:Yb³⁺/Er³⁺ microtubes (MTs) with Ag nanoparticles (NPs). A single Ag@NaYF₄ MT hybrid structure (Ag@NaYF₄ MTHS) improves SERS activity compared to a typical substrate consisting of pure Ag NPs deposited on glass slide and exhibits excellent Raman signal response to various probe molecules (4-nitrothiophenol (4-NTP), crystal violet (CV), and Rhodamine 6G (Rh6G)). Furthermore, the Ag@NaYF₄ MTHS substrate presents good catalytic performance and the plasmon-driven catalytic kinetics process is successfully monitored by using in situ SERS spectroscopy technique. This study provides valuable insights for designing multifunctional hybrid structures that incorporate containing noble metallic and lanthanide-based materials. These composite structures hold significant potential for advancing applications in photocatalysis, sensor, and in situ bio/chemical-analysis.