In situ high-temperature Raman scattering study of monoclinic Ag₂Mo₂O₇ microrods

In this work, we present a temperature-dependent behavior of monoclinic silver dimolybdate (m-Ag₂Mo₂O₇) microrods using in situ Raman scattering. The m-Ag₂Mo₂O₇ microrods were obtained by the conventional hydrothermal method at 423 K for 24 h. The structural and morphological characterization of the sample has been done by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. Temperature-dependent Raman scattering measurements were performed on m-Ag₂Mo₂O₇ microrods, and the results show an irreversible first-order structural phase transition at 698 K-723 K and the melting process at 773 K. Changes in the Raman spectra confirm the phase transition from the P2₁/c monoclinic structure to the P-1 triclinic structure. No morphological changes were observed during the structural phase transition of the sample at 723 K. Time-dependent optical microscopy at 773 K showed the growth of nanowires on the Ag₂Mo₂O₇ microrods in the triclinic structure.