Electrical and optical properties of NdAlO3 synthesized by an optimized combustion process

Nanocrystals of neodymium aluminate (NdAlO3) are synthesized using an optimized single step auto-ignition citrate complex combustion process. The combustion product was characterized by X-ray diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and Ultraviolet-visible reflection spectroscopy. The combustion product is single phase and composed of aggregates of nanocrystals of sizes in the range 20-40 nm. The NdAlO3 crystallized in rhombohedral perovskite structure with lattice parameters a = 5.3223 Å and c = 12.9292 Å. The absorption spectrum of the NdAlO3 nanocrystals shows characteristic absorption bands of the Nd atom. The polycrystalline fluffy combustion product is sintered to high density (~ 97%) at ~ 1450 °C for 4 h and the microstructure was characterized by scanning electron microscopy. The electrical properties of the sintered product were studied using dielectric measurements. The sintered NdAlO3 has a dielectric constant (εr) and a dielectric loss (tan δ) of 21.9 and ~ 10− 3 at 5 MHz, respectively.