Containing Manganese DMSs Nanostructures via a Nonaqueous Route

2009 ◽  
Vol 79-82 ◽  
pp. 533-536 ◽  
Author(s):  
Yu Liang Zhang ◽  
Xiao Feng Li
Keyword(s):  
Magnetic Properties ◽  
Room Temperature ◽  
Wurtzite Structure ◽  
Epr Spectra ◽  
G Factor ◽  
Characterization Techniques ◽  
Zno Nanocrystals ◽  
Doped Zno

The structure and the magnetic properties of 3.0 and 0.3 at.% Mn-containing ZnO-based DMSs, synthesized by a straightforward and experimentally simple nonaqueous route, have been investigated by various characterization techniques, including XRD, HRTEM, and EPR. The as-synthesized doped ZnO nanocrystals retain the wurtzite structure with a morphology in the form of flower-like shape. EPR spectra with g-factor values of 2.0023(3% at.%) and 2.0019(0.3 at.%), respectively, at room temperature were obtained, confirming that the Mn2+ is substitutionally incorporated into the ZnO nanocrystals.

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.

Room Temperature Ferromagnetism and Photoluminescence of Fe Doped ZnO Nanocrystals

2011 ◽  
Vol 115 (48) ◽  
pp. 23671-23676 ◽  
Author(s):  
Darshana Y. Inamdar ◽  
Arjun K. Pathak ◽  
Igor Dubenko ◽  
Naushad Ali ◽  
Shailaja Mahamuni
Keyword(s):  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Zno Nanocrystals ◽  
Doped Zno

Local structure investigation of (Co, Cu) co-doped ZnO nanocrystals and its correlation with magnetic properties

2016 ◽  
Vol 90 ◽  
pp. 100-113 ◽  
Author(s):  
N. Tiwari ◽  
S. Doke ◽  
A. Lohar ◽  
Shailaja Mahamuni ◽  
C. Kamal ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Local Structure ◽  
Structure Investigation ◽  
Zno Nanocrystals ◽  
Doped Zno ◽  
Co Doped

Correlation of structural and magnetic properties of Ni-doped ZnO nanocrystals

2013 ◽  
Vol 47 (4) ◽  
pp. 045308 ◽  
Author(s):  
Deepak More ◽  
Chinmay Phadnis ◽  
Sohini Basu ◽  
Arjun Pathak ◽  
Igor Dubenko ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Zno Nanocrystals ◽  
Structural And Magnetic Properties ◽  
Doped Zno

Effect of Zinc Oxide Nanocrystals in Media Containing E. coli and C. xerosis Bacteria

2005 ◽  
Vol 900 ◽  
Author(s):  
Triana Merced ◽  
Stephanie Santos ◽  
Omayra Rivera ◽  
Nicole Villalba ◽  
Yahira Baez ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Room Temperature ◽  
Cobalt Ferrite ◽  
Growth Curves ◽  
Adaptation Period ◽  
E Coli ◽  
Standard Curve ◽  
Stable Suspension ◽  
Zno Nanocrystals ◽  
Doped Zno

ABSTRACTThe present investigation is centered on the study of the growth curves of E. coli and C. xerosis bacteria in the presence of nanosize particles of Zinc Oxide. Previous works demonstrated the sensitivity of the bacteria, when these were reproduced in media that contain nanoparticles of luminescent silicon and Cobalt Ferrite. Doped ZnO nanocrystals were synthesized by conventional precipitation in ethanol solutions as reported by Spanhel and Anderson for bare ZnO. In our case, the syntheses were carried out under room-temperature conditions.The experimental results of E. coli bacteria in contact with a stable suspension of nanoparticles of Zinc Oxide, shows a growth curve without adaptation period. Moreover a short and slowly logarithmic stage has been observed, reaching the stationary stage after approximately four hours compared with one in absence of the nanoparticles (standard curve). During the observations, a change in the lifetime of the bacteria (metabolism) with particulate was noticed,as well as the beginning of the mortality stage. However, different results were recorded for silicon and ferrite. For the case of the bacteria C. xerosis, the curve with particles is above its standard curve, for all times with none of the oscillations which occured in the nanometer silicon. For these bacteria the beginning of the mortality stage is observed when they have particles. For both bacteria with Zinc Oxide nanoparticles this occurs approximately after nine hours.

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