Nanocrystalline GdBa2HfO5.5 perovskite dielectric material-A single-step synthesis and its characterization

Nanocrystals of GdBa2HfO5.5 perovskite ceramic materials, of the family A2(BB′)O6, were synthesized using an auto-igniting combustion of a precursor solution containing metal ions, oxidant and a fuel. Phase purity and particulate properties of the as-prepared powder were examined using X-ray diffraction, differential thermal and thermogravimetric analyses, Fourier-transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopic techniques. These nanocrystals were sintered to high density (∼98% of the theoretical density) at ∼1620 °C for 2 h.The sintering behavior, dielectric constant and dielectric loss factor of the samples showed variations in magnitude with that of the samples prepared by conventional solid-state route.