Mesoporous Ag@WO₃ core-shell, an investigation at different concentrated environment employing laser ablation in...

In this study, silver-tungsten oxide core-shell nanoparticles (Ag-WO₃ NPs) were synthesized by pulsed laser ablation in liquid employing a (1.06 µm) Q-switched Nd:YAG laser, at different Ag colloidal concentration environment (different core concentration). The produced Ag-WO₃ core-shell NPs were subjected to characterization using UV-visible spectrophotometry, X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive spectroscopy, electrical analysis, and photoluminescence PL. The UV-visible spectra exhibited distinct absorption peaks at around 200 and 405 nm, which attributed to the occurrence of surface Plasmon resonance of Ag NPs and WO₃ NPs, respectively. The absorbance values of the Ag-WO₃ core-shell NPs increased as the core concentrations rose, while the band gap decreased by 2.73-2.5 eV, The (PL) results exhibited prominent peaks with a central wavelength of 456, 458, 458, 464, and 466 nm. Additionally, the PL intensity of the Ag-WO₃-NP samples increased proportionally with the concentration of the core. Furthermore, the redshift seen at the peak of the PL emission band may be attributed to the quantum confinement effect. EDX analysis can verify the creation process of the Ag-WO₃ core-shell nanostructure. XRD analysis confirms the presence of Ag and WO₃ (NPs). The TEM images provided a good visualization of the core-spherical shell structure of the Ag-WO₃ core-shell NPs. The average size of the particles ranged from 30.5 to 89 (nm). The electrical characteristics showed an increase in electrical conductivity from (5.89 × 10^-4) (Ω cm)^-1 to (9.91 × 10^-4) (Ω cm)^-1, with a drop in average activation energy values of (0.155 eV) and (0.084 eV) at a concentration of 1.6 μg/mL of silver.