Preparation of hcp and fcc Ni and NiNiO Nanoparticles Using a Citric Acid Assisted Pechini-Type Method

Abstract EN

The preparation and characterization of hcp and fcc Ni and Ni/NiO nanoparticles is reported.

Ni and Ni/NiO nanoparticles were obtained starting from a precursor material prepared using a citric assisted Pechini-type method and, then, followed by a calcination of the precursor in air at either 400 or 600°C for different times.

The precursor was analyzed using thermogravimetric and differential thermal methods (TGA-DTA), and the resulting nanoparticles were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and vibrational sample magnetometry.

Nanoparticles showed a phase transformation for Ni from hcp to fcc and/or to fcc NiO structure as the calcination time increased.

The influence of the phase transition and the formation of NiO on the magnetic properties of the samples are discussed.