scholarly journals Structural, Morphological, Optical, and Room Temperature Magnetic Characterization on Pure and Sm-Doped ZnO Nanoparticles

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Khalil Badreddine ◽  
I. Kazah ◽  
M. Rekaby ◽  
R. Awad
Keyword(s):  
Crystallite Size ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Magnetic Hysteresis ◽  
Hexagonal Wurtzite Structure ◽  
Xrd Analysis ◽  
Peak Shift ◽  
Band Gap Energy ◽  
Ferromagnetic Behavior ◽  
Doped Zno

Nano crystalline Zn1-xSmxO, (0.00 ≤ x ≤ 0.10), were prepared by wet chemical coprecipitation method. The effect of samarium doping on the structural, morphological, optical, and magnetic properties of ZnO nanoparticles was examined by X-ray powder diffraction (XRD), Transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), Ultraviolet-visible spectroscopy (UV) and M-H magnetic hysteresis. XRD analysis showed the hexagonal wurtzite structure of ZnO. The absence of Sm2O3 as separate phase may be attributed to the complete dissolving of samarium in ZnO lattice. The lattice parameters (a and c) of Zn1-xSmxO were calculated and they fluctuated with the increase of Sm doping which indicated that the structure of ZnO was perturbed by the doping of Sm. The crystallite size was computed for all the samples using Debye-Scherrer’s method. The crystallite size decreased with the increase of Sm doping. TEM micrographs revealed that the size and the shape of the ZnO nanocomposites were changed by modifying the doping level of samarium. FTIR analysis spectrum confirmed the formation of ZnO phase and revealed a peak shift between pure and Sm-doped ZnO. The band gap energy and Urbach energy were calculated for Zn1-xSmxO, (0.00 ≤ x ≤ 0.10). The band energy gaps of pure and Sm doped ZnO samples are in the range 2.6–2.98 eV. M-H hysteresis inspection, at room temperature, showed that the pure ZnO exhibited a ferromagnetic behavior incorporated with diamagnetic and paramagnetic contributions. Ferromagnetic behavior was reduced for the doped samples with x=0.01 and x=0.04. The samples with x=0.02 and 0.06 ≤ x ≤ 0.10 tend to be superparamagnetic. The saturation magnetization (Ms), the coercivity (Hc), and the retentivity (Mr) were recorded for Zn1-xSmxO, (0.00 ≤ x ≤ 0.10).

Structural, Optical and Room Temperature Magnetic Study of Mn-Doped ZnO Nanoparticles

NANO ◽  
2016 ◽  
Vol 11 (04) ◽  
pp. 1650042 ◽  
Author(s):  
Majed Sharrouf ◽  
Ramadan Awad ◽  
Salem Marhaba ◽  
Douaa El-Said Bakeer
Keyword(s):  
Zno Nanoparticles ◽  
Room Temperature ◽  
Xrd Analysis ◽  
Peak Shift ◽  
Antiferromagnetic Coupling ◽  
Ferromagnetic Behavior ◽  
Two Samples ◽  
Doped Zno ◽  
Co Precipitation ◽  
Mn Doped

Undoped and Mn-doped ZnO nanoparticles (Zn[Formula: see text]MnxO), with nominal weight percentages [Formula: see text], have been synthesized by co-precipitation technique. The synthesized nanoparticles are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible spectroscopy (UV) and Fourier transform infrared spectroscopy (FTIR). From XRD analysis, the compound ZnMnO3 is formed for [Formula: see text] with cubic structure ([Formula: see text][Formula: see text]Å) and its concentration increases with x. Moreover, XRD analysis reveals the wurtzite hexagonal crystal structure for ZnO. The lattice parameters (a and c) of Zn[Formula: see text]MnxO are calculated and they increase with the doping concentration of Mn as a consequence of the larger ionic size of Mn[Formula: see text] ions compared to Zn[Formula: see text] ions. The crystallite size is calculated for all the samples using Debye–Scherrer’s method (SSM), Williamson–Hall methods (UDM, USDM and UDEDM) and Size-Strain Plot method (SSP), and the results are in good agreement with TEM. The presence of functional groups and the chemical bonding is confirmed by FTIR spectra that shows a peak shift between undoped and doped ZnO. The energy bandgap [Formula: see text] is calculated for different concentrations of Mn [Formula: see text] by using the UV-visible optical spectroscopy, between 300[Formula: see text]nm and 800[Formula: see text]nm, showing a noticeable drop in [Formula: see text] with x. At room temperature, the magnetization of the samples reveals the intrinsic ferromagnetic (FM) behavior of undoped ZnO, ferromagnetic behavior of ZnxMn[Formula: see text]O [Formula: see text] and the co-existence of ferromagnetic and paramagnetic behavior for ZnxMn[Formula: see text]O [Formula: see text]. This ferromagnetism is decreased for the doped samples as a consequence of antiferromagnetic coupling between Mn ions. The two samples correspond to [Formula: see text] and [Formula: see text], tend to be superparamagnetic because of the formation of single domain particles as a consequence of small particle size. [Formula: see text] shows an optimum value of Mn concentration for maximum saturation magnetization and the best ferromagnetic nature.

Photoluminescence and Magnetic Properties of Undoped and (Mn, Co) co-doped ZnO Nanoparticles

2020 ◽  
Vol 16 (4) ◽  
pp. 655-666
Author(s):  
Mona Rekaby
Keyword(s):  
Magnetic Properties ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Magnetic Measurements ◽  
Structural Defects ◽  
Ferromagnetic Behavior ◽  
Secondary Phases ◽  
Antiferromagnetic Ordering ◽  
Doped Zno ◽  
Co Doped

Objective: The influence of Manganese (Mn2+) and Cobalt (Co2+) ions doping on the optical and magnetic properties of ZnO nanoparticles was studied. Methods: Nanoparticle samples of type ZnO, Zn0.97Mn0.03O, Zn0.96Mn0.03Co0.01O, Zn0.95Mn0.03 Co0.02O, Zn0.93Mn0.03Co0.04O, and Zn0.91Mn0.03Co0.06O were synthesized using the wet chemical coprecipitation method. Results: X-ray powder diffraction (XRD) patterns revealed that the prepared samples exhibited a single phase of hexagonal wurtzite structure without any existence of secondary phases. Transmission electron microscope (TEM) images clarified that Co doping at high concentrations has the ability to alter the morphologies of the samples from spherical shaped nanoparticles (NPS) to nanorods (NRs) shaped particles. The different vibrational modes of the prepared samples were analyzed through Fourier transform infrared (FTIR) measurements. The optical characteristics and structural defects of the samples were studied through Photoluminescence (PL) spectroscopy. PL results clarified that Mn2+ and Co2+ doping quenched the recombination of electron-hole pairs and enhanced the number of point defects relative to the undoped ZnO sample. Magnetic measurements were carried out at room temperature using a vibrating sample magnetometer (VSM). (Mn, Co) co-doped ZnO samples exhibited a ferromagnetic behavior coupled with paramagnetic and weak diamagnetic contributions. Conclusion: Mn2+ and Co2+ doping enhanced the room temperature Ferromagnetic (RTFM) behavior of ZnO. In addition, the signature for antiferromagnetic ordering between the Co ions was revealed. Moreover, a strong correlation between the magnetic and optical behavior of the (Mn, Co) co-doped ZnO was analyzed.

Assessment of Magnetic Properties between Fe and Ni Doped ZnO Nanoparticles Synthesized by Microwave Assisted Synthesis Method

2021 ◽  
Vol 317 ◽  
pp. 119-124
Author(s):  
Sabiu Said Abdullahi ◽  
Garba Shehu Musa Galadanci ◽  
Norlaily Mohd Saiden ◽  
Josephine Ying Chyi Liew
Keyword(s):  
Magnetic Properties ◽  
Zno Nanoparticles ◽  
Room Temperature ◽  
Synthesis Method ◽  
Dilute Magnetic Semiconductors ◽  
High Coercivity ◽  
Microwave Assisted Synthesis ◽  
Ferromagnetic Behavior ◽  
Microwave Assisted ◽  
Doped Zno

The emergence of Dilute Magnetic Semiconductors (DMS) with a potentials for spintronic application have attracted much researches attention, special consideration has been given to ZnO semiconductor material due to its wide band gap of 3.37 eV, large exciting binding energy of 60 meV, moreover, its ferromagnetic behavior at room temperature when doped with transition metals. MxZn1-xO (M = Fe or Ni) nanoparticles were synthesized by microwave assisted synthesis method calcined at 600°C. The structural, morphological and magnetic properties of these nanoparticles were studied using X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Vibrating Sample Magnetometer (VSM) respectively. Single phase Wurtzite hexagonal crystal structure was observed for the undoped and Fe doped ZnO nanoparticles with no any impurity, whereas Ni doped ZnO nanoparticles shows the formation of NiO impurities. The magnetic measurement reveals a diamagnetic behavior for the undoped ZnO meanwhile a clear room temperature ferromagnetism was observed for both Fe and Ni doped ZnO. Fe doped ZnO present a high saturation magnetization compared to Ni doped ZnO. However, Ni doped ZnO present high coercivity. The research was confirmed that Fe doped ZnO material will be good material combination for spintronic applications.

Magneto-Opto Electronic Applications of Conductive and Room Temperature Ferromagnetic (Al, Mn) Co-Doped ZnO Particles with Visible Emission

2020 ◽  
Vol 20 (6) ◽  
pp. 3913-3918 ◽  
Author(s):  
Divya Rehani ◽  
Swati Bishnoi ◽  
Manish Saxena ◽  
Shailesh Narain Sharma
Keyword(s):  
Room Temperature ◽  
Annealing Temperature ◽  
Magnetic Measurements ◽  
Hexagonal Wurtzite Structure ◽  
Solid State Reaction Method ◽  
Ferromagnetic Behavior ◽  
Maximum Conductivity ◽  
Doped Zno ◽  
Mn Doped ◽  
Co Doped

The Mn, Al co-doped ZnO samples were synthesized using solid-state reaction method and were annealed in furnace at 300 °C, 600 °C and 900°C temperature. All the samples prepared were investigated in detail for analysis of their structural, morphological, optical, magnetic and electrical behavior. The XRD data confirmed the hexagonal wurtzite structure of pristine, Mn doped and Al, Mn co-doped ZnO. For morphological investigation SEM and TEM techniques were employed. The PL properties of the ZnO:Mn, Al sample revealed emission in the blue region (415–438 nm). Furthermore, IV studies were carried out to examine the conductivity of the ZnO:Mn, Al samples and maximum conductivity was found in the sample with 5% Al doping and annealing temperature 600 °C. The magnetic measurements revealed room temperature ferromagnetic behavior in the optimized ZnO:Mn, Al sample annealed at 600 °C which indicates its suitability for Magneto-Opto Electronic Applications.

A study on Cu and Ag doped ZnO nanoparticles for the photocatalytic degradation of brilliant green dye: synthesis and characterization

2016 ◽  
Vol 74 (6) ◽  
pp. 1426-1435 ◽  
Author(s):  
A. Gnanaprakasam ◽  
V. M. Sivakumar ◽  
M. Thirumarimurugan
Keyword(s):  
Zno Nanoparticles ◽  
Brilliant Green ◽  
Hexagonal Wurtzite Structure ◽  
Band Gap Energy ◽  
Precipitation Method ◽  
Zno Nps ◽  
Absorption Bands ◽  
Sem Images ◽  
Xrd Diffraction ◽  
Doped Zno

Novel polyvinyl pyrrolidone capped pure, Ag (1–3%) and Cu doped (1–3%) zinc oxide (ZnO) nanoparticles (NPs) were successfully synthesized via the co-precipitation method. The synthesized NPs were characterized by UV-visible spectrophotometry, X-ray diffraction (XRD), energy dispersive spectroscopy (EDS) and field emission scanning electron microscopy (FE-SEM). Compared to pure ZnO, the absorption bands of Ag and Cu doped ZnO NPs were shifted and, further, the band gap energy was also decreased which confirms the incorporation of Ag and Cu into the ZnO lattice. The XRD diffraction peak confirms that all the synthesized compounds are found to be of highly crystalline hexagonal wurtzite structure. In addition, the presence of Ag and Cu in the ZnO NPs was further evidenced from EDS analysis. FE-SEM images established the morphology of the doped ZnO NPs which was not affected by the addition of Ag and Cu. The photocatalytic activity of undoped, Ag doped (1–3%) and Cu doped (1–3%) ZnO NPs were tested with brilliant green dye under UV irradiation. Degradation study reveals that doping has a distinct effect on the photocatalytic behavior of ZnO NPs. In addition to that, kinetic, thermodynamic and reusability studies have been performed for the 2% Ag doped ZnO NPs.

scholarly journals Tuning of Photoluminescence and Antibacterial Properties of ZnO Nanoparticles through Sr Doping for Biomedical Applications

2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
R. Karthick ◽  
P. Sakthivel ◽  
C. Selvaraju ◽  
Mosae Selvakumar Paulraj
Keyword(s):  
Electron Microscopy ◽  
Crystallite Size ◽  
Zno Nanoparticles ◽  
Antibacterial Properties ◽  
Average Crystallite Size ◽  
Hexagonal Wurtzite Structure ◽  
Luminescence Spectra ◽  
X Ray ◽  
Doped Zno ◽  
Doping Ratio

Sr-doped ZnO nanoparticles have been synthesized using a soft chemical method. The doping ratio of Sr is varied in the range of 0 at.%, 3 at.%, and 5 at.% to 7 at.%. X-ray diffractograms revealed that the samples had hexagonal (wurtzite) structure without a trace of any mixed phase. The average crystallite size of the nanoparticles (NPs) ranged from 39 to 46 nm. The average crystallite size was increased for the initial doping (3 at.%) of Sr ions, and further increase in the doping ratio reduced the particle size due to some distortion produced in the lattice. The surface morphology of the samples and structure of the NPs were investigated using FESEM (Field Emission Scanning Electron Microscopy) and TEM (Transmission Electron Microscopy) pictures, respectively. EDX (energy-dispersive X-ray) spectroscopy confirmed the presence of strontium (Sr) in the host lattice. Photoluminescence and X-ray diffraction confirmed that the dopant ions replace some of the lattice zinc ions and that Sr2+ and Sr3+ ions coexist in the ZnO lattice. The Sr-doped ZnO exhibited violet and blue luminescence spectra at 408 nm and 492 nm, respectively. ZnO : Sr nanoparticles showed increased antibacterial activity against one gram-positive as well as one gram-negative bacteria.

Structural and Optical Properties of F-Doped ZnO Nanoparticles Synthesized by Co-Precipitation Process

2016 ◽  
Vol 675-676 ◽  
pp. 69-72
Author(s):  
Krisana Chongsri ◽  
Wanichaya Mekprasart ◽  
Wisanu Pecharapa
Keyword(s):  
Zno Nanoparticles ◽  
Fluoride Concentration ◽  
Precursor Solution ◽  
Hexagonal Wurtzite Structure ◽  
Ammonium Fluoride ◽  
Zinc Nitrate ◽  
Precipitation Process ◽  
Vis Spectroscopy ◽  
Doped Zno ◽  
Co Precipitation

In this work, we reported the preparation of F-doped ZnO nanoparticles by facile precipitation process using zinc nitrate and ammonium fluoride as starting precursors for Zn and F, respectively dissolved in deionized water. The precursor solution was prepared at various fluoride composition ranging from 1-5 wt%. The as-precipitated powders were calcined at different temperature from 500 °C to 700 °C for 2 h. Effect of calcination temperature and fluoride concentration on structural, morphologies, optical and electrical properties were investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), UV-Vis spectroscopy, respectively. XRD results indicated the complete formation of hexagonal wurtzite structure of ZnO. SEM micrographs showed the agglomeration for each sample that noticeably influenced by fluoride content.

Effect of cobalt doping on microstructures and dielectric properties of ZnO

2019 ◽  
Vol 97 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Ye Zhao ◽  
Fan Tong ◽  
Mao Hua Wang
Keyword(s):  
Zno Nanoparticles ◽  
Sol Gel ◽  
Hexagonal Wurtzite Structure ◽  
Sem Analysis ◽  
Co Doping ◽  
In Doping ◽  
Zno Powders ◽  
Doped Zno ◽  
Zno Crystal ◽  
Co Doped

Pure and cobalt-doped ZnO nanoparticles (2.5, 5, 7.5, and 10 atom % Co) are synthesized by sol–gel method. The as-synthesized nanoparticles are characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (FE-SEM) analysis. The nanoparticles of 0, 2.5, and 5 atom % Co-doped ZnO exhibited hexagonal wurtzite structure and have no other phases. Moreover, the (101) diffraction peaks position of Co-doped ZnO shift toward a smaller value of diffraction angle compared with pure ZnO powders. The results confirm that Co ions were well incorporated into ZnO crystal lattice. Simultaneously, Co doping also inhibited the growth of particles, and the crystallite size decreased from 43.11 nm to 36.63 nm with the increase in doping concentration from 0 to 10 atom %. The values of the optical band gap of all Co-doped ZnO nanoparticles gradually decreased from 3.09 eV to 2.66 eV with increasing Co content. Particular, the dielectric constant of all Co-doped ZnO ceramics gradually increased from 1.62 × 103 to 20.52 × 103, and the dielectric loss decreased from 2.36 to 1.28 when Co content increased from 0 to 10 atom %.

The Room Temperature Ferromagnetism of (N, Co) Co-Doped ZnO Nanopaticles

2014 ◽  
Vol 577 ◽  
pp. 19-22
Author(s):  
Ping Cao ◽  
Yue Bai ◽  
Zhi Qu
Keyword(s):  
Zno Nanoparticles ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Crystal Lattices ◽  
Grown Sample ◽  
N Doping ◽  
Doped Zno ◽  
Zno Crystal ◽  
Zno Nanopaticles ◽  
Co Doped

Co-doped ZnO nanoparticles were fabricated by an electrodeposition method. The XPS results show Co ions have doped into the ZnO crystal lattices successfully. The as-grown sample has no ferromagnetism at room temperature. But after an ammine plasma treatment the room temperature ferromagnetism were detected on Co0.04Zn0.96O nanoparticles. The Hall measurement reveals after the treatment the resistivity increase by three orders of magnitude. Although the aspect conductivity is n type, some holes generated by N doping play an important role to induce the ferromagnetic properties for Co doped ZnO sample.

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