Synthesis of hollow nanostructured nickel oxide microspheres by ultrasonic spray atomization

Abstract NiO nanostructured powders were synthesized by an ultrasonic spray pyrolysis (USP) technique. The powders were characterized using low temperature adsorption (BET), X-ray diffraction, scanning electron microscopy (SEM), and a transmission electron microscopy (TEM). The final product of the ultrasonic spray pyrolysis is hollow microspheres with 5–7 μm in diameter. The microspheres are built from nanoparticles with 40–60 nm in diameter.