Influence of finite size and surface effects on the structural, electrical and magnetic properties of nanostructured nickel oxide

A detailed study on the influence of crystallite size variation on the structural, electrical and magnetic properties of nickel oxide nanoparticles is reported here. The characterization techniques reveal the structural modification of the samples which resulted from the variation in crystallite size. The grain boundaries and triple junctions in the interfacial regions play a pivotal role in deciding the transport properties of nanocrystalline NiO. The dielectric measurements confirm high value of dielectric constant for NiO nanoparticles at low frequency, which can be used for the fabrication of gate dielectric in metal oxide semiconductor field effect transistors. The superparamagnetic behaviour of samples with a size ~ 8 nm points out the significance of surface atoms and uncompensated surface spins. The results highlight the role of finite size and surface effects in determining the properties of nanostructured nickel oxide.