Metal-urea complexes as primary precursors to generate VO2, ZrO2, NbO2, TaO2, Ga2O3 and TeO2 oxides in the nanoscale range by thermal decomposition route

Abstract

Six metal chlorides of vanadium, zirconium, niobium, tantalum, gallium, and tellurium (i.e., VCl₃, ZrOCl₂×8H₂O, NbCl₅, TaCl₅, GaCl₃, and TeCl₄) were reacted with urea (referred to as U) in aqueous media at ~ 50 ^oC. The resulting metal-urea complexes were characterized using CHN elemental analyses, infrared (IR) spectroscopy, and thermogravimetry. After the synthesized metal-urea complexes were characterized, their ability to form stable metal oxides was examined. The vanadium(IV) oxide; VO₂, zirconium(IV) oxide; ZrO₂, niobium(IV) oxide, NbO₂, tantalum(IV) oxide; TaO₂, gallium(III) oxide; Ga₂O₃, and tellurium(IV) oxide; TeO₂, were generated by the thermal decomposition route of the synthesized metal-urea complexes at low temperature 600 °C in static air atmosphere. The transmission electron microscopy (TEM) revealed that the oxides contain uniform spherical nanoparticles.

KEY WORDS: Metal chloride, Metal-urea complex, Urea, FTIR, TEM

Bull. Chem. Soc. Ethiop. 2024, 38(4), 1003-1012.                                                          

DOI: https://dx.doi.org/10.4314/bcse.v38i4.15