Ferromagnetism in chemically synthesized<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">Ce</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>nanoparticles by Ni doping

Thurber, Aaron; Reddy, K. M.; Shutthanandan, V.; Engelhard, Mark H.; Wang, Chong M.; Hays, J.; Punnoose, Alex

doi:10.1103/physrevb.76.165206

Cited by 163 publications

(71 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In addition to oxygen vacancies, TM doping has been shown to increase the RTFM of ceria NPs (6)(7)(8)(9)(10)(11)(12)(13). There are at least two possible mechanisms for RTFM enhancement by TM doping: creation of oxygen vacancies by introduction of a different-valance dopant into the host lattice and ferromagnetic ordering of a TM dopant.…”

Section: Introductionmentioning

confidence: 99%

Concentration dependence of magnetic moment in Ce1-xFexO2

Beausoleil

Thurber

Rao

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

In this study, we examined the impact of iron doping on the structural, chemical, and magnetic properties of ceria (Ce 1-x Fe x O 2 ). Samples were produced in triplicate through a coprecipitation approach in a forced hydrolysis synthesis that yielded consistently sized nanocrystals, using three different cerium precursors: cerium chloride, cerium ammonium nitrate and cerium nitrate. Particles were characterized by x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR) spectroscopy and vibrating sample magnetometry (VSM). XRD showed the average crystallite size to be 4.4 ± 1.2 nm, which agreed well with TEM data. XPS and EPR data shows iron to be in the Fe 3+ state and confirms the nominal dopant concentration. The moment per Fe ion found was largest at the lowest dopant concentrations, with values of 0.078 and 0.055 µ B /Fe ion for 0.1 and 0.5% Fe, respectively, which quickly decreased as the concentration was increased. We used XPS to estimate Ce 3+ /Ce 4+ ratio to be in the 0.2-0.3 range and observed a linear relation between the saturation magnetization and the Ce 3+ /Ce 4+ ratio.Introduction:

show abstract

Section: Introductionmentioning

confidence: 99%

Concentration dependence of magnetic moment in Ce1-xFexO2

Beausoleil

Thurber

Rao

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…[1][2][3][4][5][6][7][8][9][10][11] The reported variations in the results and conclusions are quite controversial; however, it seems the magnetism observed in oxide nanoparticles may be affected by particle size, grain boundary area, defects, surfactant coating and/or doping. 9,10,[12][13][14][15] Upon revisiting samples which had been previously prepared, we noted that the estimated crystallite size had increased after several years.…”

Section: Introductionmentioning

confidence: 99%

Unusual crystallite growth and modification of ferromagnetism due to aging in pure and doped ZnO nanoparticles

Thurber

Alanko

Beausoleil

et al. 2012

Journal of Applied Physics

View full text Add to dashboard Cite

We report the unusual growth of pure and Fe doped ZnO nanoparticles prepared by forced hydrolysis, and the weakening of ferromagnetism due to aging in ambient conditions. More than four dozen nanoparticle samples in the size range of 4 -20 nm were studied over 1 to 4 years. The as-prepared samples had significant changes in their crystallite sizes and magnetization as they aged in ambient conditions. Detailed studies using x-ray diffraction and transmission electron microscopy (TEM) demonstrated that the crystallite size increased by as much as 1.4 times. Lattice parameters and strain also showed interesting changes. Magnetometry studies of Zn 1-x Fe x O with x = 0-0.2 showed ferromagnetism at room temperature; however, keeping the samples in ambient conditions for one year resulted in modifications in the crystallite size and magnetization. For the Zn 0.95 Fe 0.05 O sample, the size changed from 7.9 nm to 9.0 nm, while the magnetization decreased from 1 memu/g to 0.2 memu/g . Both magnetic and structural changes due to aging varied with the environment in which they were stored, indicating that these changes are related to the aging conditions.

show abstract

“…Once an electron is trapped in Ce 4+ ion, a transitions between 5d and 4f orbitals become possible [25], which could take part in an electron signal in the ESR spectrum. To compensate for the charge imbalance, the oxygen vacancy was formed [27,28].…”

Section: Resultsmentioning

confidence: 99%

Characteristics and Photocatalytics Activities of Ce-Doped ZnO Nanoparticles

Djaja¹,

Saleh²

2013

MSA

View full text Add to dashboard Cite

Ce-doped ZnO nanoparticles with various doping concentrations of cerium ion were prepared by the co-precipitation method. All prepared nanoparticles were characterized by electron spin resonance (ESR), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and UV-Vis diffuse reflectance spectroscopy. All nanoparticles show X-ray diffraction pattern that matched with ZnO in its wurzite structure and average grain size was in the range of 13 -16 nm. UV-Vis measurements indicated a red shift of the photophysical response of ZnO after doping that was exhibited in reflection spectra in the visible region between 300 -800 nm. In addition, it has been found from electron spin resonance measurements that defects, which are likely to be oxygen vacancy and an electron trapped at cerium site are formed in our Ce-doped ZnO particles. Photocatalytic activities of Ce-doped ZnO were evaluated by irradiating the nanoparticles solution to ultraviolet light by taking methyl orange as organic dye. The experiment demonstrated that the photodegradation increased as doping concentrations increased at first and then decreased when the doping concentration exceeded 9 at%. It is proposed that the photocatalytic activity is strongly dependent on the formation of oxygen vacancy and an electron trapped at cerium site.

show abstract

Ferromagnetism in chemically synthesizedCeO2nanoparticles by Ni doping

Cited by 163 publications

References 41 publications

Concentration dependence of magnetic moment in Ce1-xFexO2

Concentration dependence of magnetic moment in Ce1-xFexO2

Unusual crystallite growth and modification of ferromagnetism due to aging in pure and doped ZnO nanoparticles

Characteristics and Photocatalytics Activities of Ce-Doped ZnO Nanoparticles

Contact Info

Product

Resources

About