Cu- and Ni-Doping Effect on Structure and Magnetic Properties of Fe-Doped ZnO Nanoparticles

Abstract

Cu-and Ni-codoped FeZnO particles with the wurzite structure were successfully synthesized at low temperature by a co-precipitation method. The samples were characterized using a vibrating sample magnetometer, X-ray diffraction, energy dispersive X-ray spectroscopy, UV-Vis spectrophotometry and electron spin resonance. The results demonstrated that room temperature ferromagnetic order was observed in both samples and the magnetization was higher than that of Fe-doped ZnO. The correlation between the structural and magnetic properties is discussed. Figure 4. The room temperature ferromagnetic of Zn 0.96 Fe 0.01 Cu 0.03 O and Zn 0.96 Fe 0.01 Ni 0.03 O compared with Zn 0.95 Fe 0.05 O, n 0.94 Cu 0.06 O, and Zn 0.95 Ni 0.05 O nanoparticles. Z

Microwave combustion synthesis of hexagonal prism shaped ZnO nanoparticles and effect of Cr on structural, optical and electrical properties of ZnO nanoparticles

“…7(aee) shows the TEM images and selected area of electron diffraction (SAED) patterns of the ZnO and Cr doped ZnO (8 wt %) prepared by simple microwave combustion method and calcinated at 500 C. The micrographs shows good crystalline nature and reveals particle size ranges from 38 to 62 nm for ZnO and 30e50 nm for Cr-ZnO. This is well matched with the crystal size calculated from XRD using Scherrer's formula [30]. The SAED patterns reveal the qualitative difference between the samples ZnO and Cr-ZnO.…”

“…3 depicts the relation between full width at half maximum, micro-strain and crystalline size for undoped and Cr doped ZnO nanoparticles, which are calculated from the XRD data (Table 1). This revealed that FWHM is directly proportional to micro-strain and inversely proportional to crystalline size, i.e., for all the samples, as the FWHM of (100) and (002) peaks were increased simultaneously in the lattice strain and decrease in crystalline size or vice-versa [30]. The average crystalline size was calculated from the Scherrer's equation [31]:…”

Observation of ferromagnetism at room temperature in polycrystalline Zn1 − x Fe x O solid solutions synthesized by the precursor method

“…Therefore, the development of new synthesis methods, which make it possible not only to control the degree of dispersion of nanopowders but also to synthesize samples of desired composition and imperfection and, consequently, samples with a speci fied set of magnetic characteristics, remains an impor tant problem. At present, there are the following most frequently used approaches to the synthesis of Zn 1 ⎯ x M x O: (1) solid phase synthesis [15], (2) self propagating high temperature synthesis [17], (3) sol vothermal (hydrothermal) synthesis [18,19], (4) solgel synthesis [20], (5) synthesis by precipitation from a solution in the form of a hydroxide or directly in the form of Zn 1 -x M x O [8,21], (6) microwave assisted synthesis [14,21], and (7) mechanochemical synthesis [22].…”

“…The range of potential appli cations of ZnO is extensive and includes oxidation photocatalysts, gas sensors, plane field displays, ultra thin flexible screens, light emitting diodes, phos phors, high speed scintillators, varistors, substrates for the preparation of gallium nitride thin films, and so on [1][2][3][4][5]. Increased interest in zinc oxide doped with cat ions of ferromagnetic metals, such as manganese, iron, cobalt, and nickel, is caused by the need to search for new magnetic materials for spin electronics, which have opened the prospect of the development of magnetoresistive random access memory cells, spin light emitting diodes and field effect transistors, mag netic field sensors, and elements of quantum comput ers [4,[6][7][8]. Although such materials as Zn 1 -x M x O solid solutions contain only a few atomic percent of magnetic impurities with a negligible exchange inter action, they can exhibit ferromagnetism even at room temperature [9][10][11].…”

Room-temperature ferromagnetism in polycrystalline Zn1–xFexO (0≤x≤0.075) solid solutions synthesized by the precursor method

“…Therefore, the development of novel synthesis methods allows not only to control the degree of dispersion of nanopowders, but also to produce samples with a pre-assigned composition and imperfection and consequently with complex magnetic characteristics, which remains a topical problem to date. At present, the most commonly used approaches for the synthesis of Zn 1ex Fe x O are: а) solid-phase synthesis [15]; b) high-temperature self-propagating synthesis [17]; c) solvothermal (hydrothermal) synthesis [18,19]; d) solegel synthesis [20]; and e) synthesis by deposition from a solution in the form of hydroxide or directly as Zn 1ex Fe x O [8].…”