Structural and Optical Properties of Non-Stoichiometric Bi4Six/2Snx/2V2-xO11-3x/4 (0.1 ≤ x ≤ 0.5)
Résumé
The non-stoichiometric solid solution Bi4Six/2Snx/2V2-xO11-3x/4 (where 0.1 ≤ x ≤ 0.5), referred to as BiSiSnVOx, was synthesized via the conventional solid-state reaction method. The resulting materials were subjected to comprehensive structural and microstructural characterization using X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy combined with energy-dispersive X-ray spectroscopy. X-ray diffraction analyses performed at room temperature and as a function of temperature confirmed the presence of three crystalline phases: α, β, and γ. These results were confirmed by Raman and infrared spectroscopic data. Scanning electron microscopy images revealed a dense microstructure with well-defined grains. Furthermore, the optical band gap of BiSiSnVOx was found to decrease from 2.08 electron volts (for x = 0.1) to 1.91 electron volts (for x = 0.4), indicating enhanced absorption in the visible range and promising potential in photocatalytic applications.