Structural, optical and magnetic properties of Ni-doped ZnO micro-rods grown by the spray pyrolysis method

Abstract

Undoped and Ni-doped ZnO micro-rod arrays were successfully synthesized by the spray pyrolysis method on glass substrates. Analysis of the samples with x-ray diffraction and scanning electron microscopy showed that these micro-rod arrays had a polycrystalline wurtzite structure with a highly c-axis preferred orientation. Photoluminescence studies at both 300 K and 10 K show that the incorporation of nickel leads to a relative increase in the visible blue light band intensity. Magnetic measurements indicated that Ni-doped ZnO samples exhibit ferromagnetic behavior at room temperature, which is possibly related to the presence of point defects.

Effect of Ni-doping on the structural, optical and magnetic properties of ZnO nanoparticles by solvothermal method

“…The intensity of the peak (626 nm) due to oxygen defects decreases with increasing Ni doping concentration which shows there may be some recombination occur [41]. Fig.…”

“…[35,41]. Liu et al reported that NiO is an antiferromagnetic material with Neel temperature of 520K, while at room temperature it is super paramagnetic [44].…”

Shape-controlled magnetic nanoplatelets of Ni-doped ZnO synthesized via a chemical precursor

“…Further observations reveal that all the peaks gradually diminish with the increase in Ni concentration due to quenching effect [64][65][66], with the pristine ZnO sample showing the most intense bands. Yilmaz et al also observed similar decrease in the intensity of the emission peaks with the increase in Ni content in rod-shaped particles of Ni-doped ZnO synthesized by spray pyrolysis [67]. The increase in Ni concentration leads to increase in the impurities at Zn sites.…”

Growth of Co-doped ZnO nanoparticles by porous alumina assisted sol–gel route: Structural optical and magnetic properties

“…However, in many reports the as observed magnetic moment value is comparatively low (of the order of micro to mili emu/g) even for higher percentage of TM doping [11,12,23]. Also the FM to PM transition temperature (T C ) is not high in many cases [21,22]. In this scenario, synthesis of TM doped ZnO nanoparticles showing FM above room temperature with a high moment, high crystallinity and high T C still remains a significant challenge for future spintronic devices.…”

“…Many researchers have tried to synthesize ZnO based DMS nanostructure [16,21,22]. However, in many reports the as observed magnetic moment value is comparatively low (of the order of micro to mili emu/g) even for higher percentage of TM doping [11,12,23].…”