Synthesis of nanocrystalline NiO by sol-gel and homogeneous precipitation methods

Abstract

Nanocrystalline nickel oxide has been prepared via thermal decomposition of precursors obtained using two methods, sol-gel process and homogeneous precipitation. The precursors and the oxide obtained by calcination are characterized by various analytical techniques such as powder X-ray diffraction, thermal gravimetric analysis, FT-IR spectroscopy, surface area measurements, scanning electron microscopy, transmission electron microscopy and magnetic measurements. The crystallite size of nickel oxide prepared from homogeneous precipitation method is ~ 2 nm whereas that of the nickel oxide prepared from sol-gel process is about 19 nm. The nanocrystalline NiO samples obtained by both the methods exhibit superparamagnetic behavior.