Sonochemical and solvothermal synthesis of methanol {2-[(2-hydroxy-1,1-dimethyl-ethylimino)-methyl]phenolato}-dioxidomolybdenum(VI) complex and its decomposition to MoO3 nanoparticles

Abstract

As a new precursor to prepare nano molybdenum trioxide, methanol {2-[(2-hydroxy-1,1-dimethylethylimino)-methyl]phenolato}dioxidomolybdenum(VI) complex (1) with the Schiff base ligand (H₂L) is synthesized by two different methods: solvothermal and sonochemical. Nanoparticles of 1 are obtained by one-pot solvothermal treatment of methanolic solutions of the ligand and di-oxomolybdenyl acetylacetonate at 150°C for 24 h and for improving the quality of nanostructures by sonochemical method with two types of solvents, different concentrations of initial reagents and also different sonication times. The thermal stability of nanosized compound 1 is studied by thermal gravimetric (TG) analysis and differential scanning calorimetry (DSC). Nanoparticles of orthorhombic α-MoO₃ are obtained by calcination of nanostructures of compound 1 at 700°C. All compounds and the obtained molybdenum trioxide nanostructures are characterized by elemental analysis, FT-IR, UV-Vis spectroscopy, X-ray powder diffraction (XRD), and scanning electron microscopy (SEM).