Synthesis, structural, vibrational and electrical properties of silver- and aluminum-doped molybdenum trioxide (α-MoO3)

In this work, we synthesized and characterized pure α-MoO 3 crystals and α-MoO 3 crystals doped with silver (Ag) and aluminum (Al) . α-MoO 3 crystals ware obtained using the thermal decomposition of ammonium heptamolybdate at 350 °C for 4 h. X-ray diffraction (XRD) confirmed the formation of a single-phase orthorhombic structure for all doped α -MoO 3 crystals. Quantitative analysis of the diffraction patterns using Rietveld refinement elucidated the effects of dopant incorporation on the lattice parameters. Microstructural analysis by scanning electron microscopy (SEM) revealed hierarchical rod-like morphologies. Raman and Fourier-transform infrared (FT-IR) spectroscopy showed noticeable changes in the vibrational modes after Ag and Al incorporation into the α -MoO 3 lattice. UV-Vis spectroscopy demonstrated bandgap variations in the 3.1–3.4 eV range. DC electrical measurements confirmed the semiconducting behavior of the doped crystals, with enhanced conductivity observed at lower dopant concentrations (1.0% Ag, 0.5% Al).