Synthesis and characterization of NixMg1−xAl2O4 nano ceramic pigments via a combustion route

MgAl2O4 was successfully used as a crystalline host network for the synthesis of nickel-based nano cyan refractory ceramic pigments. Different compositions of NixMg1−xAl2O4 (0.1 ⩽ x ⩽ 0.8) powders have been prepared by using a low temperature combustion reaction (LTCR) of the corresponding metal nitrates with urea (U) as a fuel at 300 °C in an open air furnace. The as-synthesized samples were characterized by thermal analysis (TG-DTG/DTA), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). UV–Vis and diffuse reflectance spectroscopy (DRS) using CIE- L∗a∗b∗ parameters methods have been used for color measurements. The results show that the NixMg1−xAl2O4 samples are the crystalline phase with a particle size of 8.85–43.66 nm in the temperature range 500–1200 °C. The density, particle size, shape and color are determined for all the prepared samples with different calcination times and temperatures.

The morphology and microstructure of nano ceramic pigments have been characterized by using transmission electron microscopy (TEM) photographs of powder samples. Spherical particles for 0.10, 0.50 and 0.80 mol Ni2+ systems have been observed. Also, the average of the particle sizes of nano-ceramic pigments have been measured by TEM. The morphology and particle size decrease on increasing the amount of doping by the Ni2+ ion. The particle sizes are calculated using an ultra structure size calculator or by quantitative electron microscopy using a real analysis. Measurements of at least 20 particles were required to characterize each size distribution from the TEM photographs.Figure optionsDownload as PowerPoint slideResearch highlights
► NixMg1-xAl2O4 has been successively prepared by low temperature combustion method.
► Particle sizes in the range of 8.85–43.66 nm were obtained.
► Color intensity increased as the amount of nickel increased and calcination temperatures and time.