H Arabi - Department of Physics, Faculty of science, University of Birjand
F Mashayekhi

The various kinds of Ni compounds have different magnetic properties. It is well known that the magnetic properties of bulk materials are different from the nanomaterials [1].Magnetism of small particles has generated increasing interest due to their unique magnetic properties as well as their technological application[2] for example NiO nanoparticles are desirable for many applications such as in the manufacture of electrochoromic films, magnetic materials, p-type transparent conducting films, gas sensors, catalyst, alkaline batteries cathode etc [3]. In this paper NiO nanoparticles surrounded by amorphous SiO2 was produced by precipitation method. The effect of various parameters such as molar ratio of Ni and Si (NNi/NSi: 1, 1.05, 1.15 and 1.24), calcination temperature, the order of mixing two solutions and also the speed of mixing the solutions have been investigated. Apart from them, we have studied the magnetic properties of produced NiO nanoparticles in two cases, (a) - Calcination of Ni (OH)2 precursor in air and, (b) -Using oxygen atmosphere in the calcinations process