Dielectric and magnetic properties of nanoporous nickel doped zinc oxide for spintronic applications

Nanoporous Ni doped ZnO is prepared in the configuration NiO(x)center dot ZnO((1-x)) (x = 0, 0.02, 0.04, 0.06, 0.08 and 0.10) using sol-gel combustion technique. The crystal structure, morphology, elemental composition, magnetic and dielectric properties of NiO(x)center dot ZnO(1-x) are determined from XRD, FE-SEM with EDX, VSM and LCRQ meter, respectively. XRD investigation confirms the presence of wurtzite hexagonal structure of ZnO in all the prepared samples. At low doping level of Ni, the crystal structure remains identical to ZnO meanwhile some structural imperfection is observed on increasing the doping concentration. FESEM images indicate the occurrence of nanopores distributed uniformly in the NiO(x)center dot ZnO(1-x). Magnetic characteristics of the samples found enhanced with increasing dopant concentration till x = 0.06. The possible explanation for the origin of the dielectric and magnetic behaviours of NiO(x)center dot ZnO(1-x) are discussed. Based on the obtained results, NiO(0.06)center dot ZnO(0.94) is a suitable candidate for Diluted Magnetic Semiconductors for spintronic applications.