scholarly journals Effects of Copper Dopants on the Magnetic Property of Lightly Cu-Doped ZnO Nanocrystals

Nanomaterials ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1578
Author(s):  
Zhi Wang ◽  
Wenzhen Xiao ◽  
Mengmeng Tian ◽  
Neng Qin ◽  
Haidong Shi ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Solution Method ◽  
X Ray Diffraction ◽  
Cu Doping ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Doped Zno ◽  
Ferromagnetic Ordering ◽  
Cu Ions ◽  
Effect Of Light

To explore the origin of magnetism, the effect of light Cu-doping on ferromagnetic and photoluminescence properties of ZnO nanocrystals was investigated. These Cu-doped ZnO nanocrystals were prepared using a facile solution method. The Cu2+ and Cu+ ions were incorporated into Zn sites, as revealed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). At the Cu concentration of 0.25 at.%, the saturated magnetization reached the maximum and then decreased with increasing Cu concentration. With increasing Cu concentration, the photoluminescence (PL) spectroscopy indicated the distribution of VO+ and VO++ vacancies nearly unchanged. These results indicate that Cu ions can enhance the long-range ferromagnetic ordering at an ultralow concentration, but antiferromagnetic “Cu+-Vo-Cu2+” couples may also be generated, even at a very low Cu-doping concentration.

Preparation and Characterization of Skin-Colored N-Doped ZnO Nanocrystals

2010 ◽  
Vol 663-665 ◽  
pp. 243-246
Author(s):  
Han Mei Hu ◽  
Chong Hai Deng ◽  
Qiang Fang ◽  
Ya Gao ◽  
Meng Wei Song
Keyword(s):  
Photoelectron Spectroscopy ◽  
X Ray Diffraction ◽  
Visible Absorption ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Uv Visible ◽  
Doped Zno ◽  
20 Nm ◽  
Strong Absorption Peak

In this paper, we report a simple two-step approach (microwave-calcinating) to prepare skin-colored N-doped ZnO nanocrystals. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS) and UV-visible absorption were used to characterize the as-synthesized products. The FESEM results reveal the products mainly take on the morphology of porous flake constructed by 20 nm nanoparticles. UV-Vis spectrum shows a strong absorption peak located at 384nm.

Magnetic Properties of Bulk Zn0.95-XMnXFe0.05O2 Prepared by Sol-Gel Method and Subsequent Hot Pressing

2011 ◽  
Vol 268-270 ◽  
pp. 356-359 ◽  
Author(s):  
Wen Song Lin ◽  
C. H. Wen ◽  
Liang He
Keyword(s):  
Magnetic Properties ◽  
Photoelectron Spectroscopy ◽  
Raw Materials ◽  
Sol Gel ◽  
Secondary Phase ◽  
X Ray Diffraction ◽  
Gel Method ◽  
X Ray ◽  
Sol Gel Method ◽  
Doped Zno

Mn, Fe doped ZnO powders (Zn0.95-xMnxFe0.05O2, x≤0.05) were synthesized by an ameliorated sol-gel method, using Zn(CH3COO)2, Mn(CH3COO)2and FeCl2as the raw materials, with the addition of vitamin C as a kind of chemical reducer. The resulting powder was subsequently compacted under pressure of 10 MPa at the temperature of 873K in vacuum. The crystal structure and magnetic properties of Zn0.95-xMnxFe0.05O2powder and bulk samples have been investigated by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). X-ray photoelectron spectroscopy (XPS) was used to study chemical valence of manganese, iron and zinc in the samples. The x-ray diffraction (XRD) results showed that Zn0.95-xMnxFe0.05O (x≤0.05) samples were single phase with the ZnO-like wurtzite structure. No secondary phase was found in the XRD spectrum. X-ray photoelectron spectroscopy (XPS) showed that Fe and Mn existed in Zn0.95-xMnxFe0.05O2samples in Fe2+and Mn2+states. The results of VSM experiment proved the room temperature ferromagnetic properties (RTFP) of Mn, Fe co-doped ZnO samples.

Characterization on the Microstructures and Optical Performances of TiO2 Doped with Transition Metals

2014 ◽  
Vol 887-888 ◽  
pp. 388-394 ◽  
Author(s):  
Xin Hua Liu ◽  
Yi Deng ◽  
Yu Chuan Zhang ◽  
Yin Hang Zhou
Keyword(s):  
Transition Metal ◽  
Metal Ions ◽  
Photoelectron Spectroscopy ◽  
Transition Metal Ions ◽  
Ultraviolet Region ◽  
Visible Light Region ◽  
X Ray Diffraction ◽  
X Ray ◽  
Light Region ◽  
Cu Ions

The structures and optical performances of TiO2doped with 4thperiodic transition metal ions were investigated in this paper. The characterization results of X-ray photoelectron spectroscopy and X-ray diffraction showed that the transition metal ions existed in oxidative states, and composites formed because of the reaction between doped metal ions and TiO2. The absorption spectroscopy of TiO2doped with zinc was mainly in ultraviolet region, close to that of the pure TiO2. While for TiO2doped with other transition metal ions including V, Cr, Mn, Fe, Co, Ni and Cu ions, the absorption spectroscopies covered ultraviolet region and visible light region, much broader than that of the pure TiO2.

A study of adsorption and absorption mechanisms of copper in palygorskite

Clay Minerals ◽  
2008 ◽  
Vol 43 (2) ◽  
pp. 195-203 ◽  
Author(s):  
Y. F. Cai ◽  
J. Y. Xue
Keyword(s):  
Photoelectron Spectroscopy ◽  
Esr Spectra ◽  
X Ray Diffraction ◽  
X Ray ◽  
Tetrahedral Sites ◽  
Octahedral Cation ◽  
Spin Resonance ◽  
Before And After ◽  
Cu Ions ◽  
Complex Ion

AbstractDesorption experiments performed on four Cu-adsorbed palygorskites suggest that the leached Cu2+ ion originates at the surface and/or net-like interstice of the palygorskite fibres. The leached fraction, calculated from the quantities of adsorbed Cu2+ before and after desorption, is <1%. This may indicate that the majority of Cu is in inaccessible structural sites. X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared (FTIR) spectroscopy and electron spin resonance (ESR) were used to determine the mineralogical character of the Cu-adsorbed palygorskite. Two photoelectron lines at 932.5 and/or 933.7 eV in the narrow scan Cu 2p3/2 spectra show that Cu adsorbed on the surface of palygorskite is in the Cu+ and Cu2+ state. The stretching vibrations of the octahedral cation shift ~3–5 cm–1 towards a greater wavenumber in the FTIR spectra of Cu-adsorbed palygorskite. It can be deduced that the Cu2+ is trapped in the channel of the palygorskite structure. The ESR spectra of the palygorskite give g values of 2.34, 2.12, 2.08 and 2.05, suggesting that some Cu ions cannot be reached by H+. These results confirm that Cu is adsorbed by palygorskite via three possible mechanisms: (1) the Cu is adsorbed onto the surface or in a net-like interstice, and its oxidation states are +1 and +2; (2) Cu forms a complex ion – [Cu(H2O)4]2+ or [Cu(H2O)6]2+, and is trapped in the channel; or (3) Cu enters into the hexagonal channel of the tetrahedral sites or the unoccupied octahedral sites of palygorskite.

Synthesis and Excellent Microwave Absorption Properties of ZnO/Fe3O4/MWCNTs Composites

NANO ◽  
2016 ◽  
Vol 11 (12) ◽  
pp. 1650139 ◽  
Author(s):  
Lei Wang ◽  
Honglong Xing ◽  
Zhenfeng Liu ◽  
Ziyao Shen ◽  
Xiang Sun ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Microwave Absorption ◽  
Photoelectron Spectroscopy ◽  
Wave Attenuation ◽  
Impedance Matching ◽  
Interfacial Polarization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Zno Nanocrystals ◽  
Transmission Electron

ZnO nanocrystals were introduced into Fe3O4/MWCNTs composites to improve the impedance matching and electromagnetic (EM) wave attenuation of the system. The as-synthesized ZnO/Fe3O4/MWCNTs composites were characterized by X-ray diffraction, vibrating sample magnetometer, field-emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy. SEM and TEM images showed that Fe3O4 microspheres 100–200[Formula: see text]nm in size connected MWCNTs. Analysis of EM parameters revealed that the impedance matching of the ZnO/Fe3O4/MWCNTs composites was considerably improved after ZnO nanocrystals were introduced. The ZnO/Fe3O4/MWCNTs composites exhibited a highly efficient microwave absorption (MA) capacity within the tested frequency range of 2–18[Formula: see text]GHz. The optimal reflection loss of EM waves was [Formula: see text][Formula: see text]dB at 6.08[Formula: see text]GHz with an absorber thickness of 3.5[Formula: see text]mm. The excellent MA properties of the composites could be attributed to the improved impedance matching, interfacial polarization, and combined effects of dielectric and magnetic losses.

scholarly journals Study Self-cleaning of Congo Red from Cotton Fabric Loaded by Zno-Ag

2015 ◽  
Vol 7 (2) ◽  
pp. 39 ◽  
Author(s):  
Amjed Oda ◽  
Hameed Ali ◽  
Abbas Lafta ◽  
Hussein Esmael ◽  
Ali Jameel ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Congo Red ◽  
Industrial Wastewater ◽  
Dye Removal ◽  
Irradiation Time ◽  
X Ray Diffraction ◽  
Reaction Parameters ◽  
X Ray ◽  
Doped Zno ◽  
Effect Of Light

The current work involves modification of zinc oxide by doping silver, this was achieved by photodeposition method. Modified zinc oxide was investigated using X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Both of ZnO and Ag doped ZnO was fabricated on a cotton texture. The photocatalytic activity of these materials was investigated by following the decolorization of congo red from simulated industrial wastewater. The decolorization of congo red over fabricated-ZnO-Ag was more efficient in comparison with non- fabricated catalysts. Different reaction parameters were undertaken including the effect of pH of the solution, irradiation time and the effect of light intensity. Complete dye removal over fabricated materials took three hours while it took 4.5 for non-fabricated materials.

Effect of N and P codoping on ZnO properties

2013 ◽  
Vol 645 ◽  
pp. 64-67 ◽  
Author(s):  
Jin Zhong Wang ◽  
Elangovan Elamurugu ◽  
Hong Tao Li ◽  
Shu Jie Jiao ◽  
Lian Cheng Zhao ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Atomic Ratio ◽  
Zno Films ◽  
X Ray Diffraction ◽  
Nitrogen And Phosphorus ◽  
X Ray ◽  
Co Doping ◽  
Glass Substrates ◽  
Doped Zno ◽  
Co Doped

Nitrogen and Phosphorus co-doped (N+P)- zinc oxide (ZnO) films were RF sputtered on corning glass substrates at 350 °C and comparatively studied with undoped, N-, and P- doped ZnO. X-ray diffraction spectra confirmed that the ZnO structure with a preferred orientation along direction. Scanning electron microscope analysis showed different microstructure for the N+P co-doping, and thus probably confirming the co-existence of both the dopants. X-ray photoelectron spectroscopy spectra revealed that the chemical composition in N+P co-doped ZnO are different from that found in undoped, N-, and P- doped ZnO. The atomic ratio of N and P in N+P co-doped ZnO is higher than that in single N or P doped ZnO. One broad ZnO emission peak around 420 nm is observed in photoluminescence spectra. The relative intensity of the strongest peak obtained from co-doped ZnO films is about twice than the P- doped and thrice than the pure and N- doped films.

scholarly journals Facile Synthesis of Electroconductive AZO@TiO2Whiskers and Their Application in Textiles

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Hui Ma ◽  
Qiang Gao ◽  
Chunxia Gao ◽  
Wei Bao ◽  
Mingqiao Ge
Keyword(s):  
Electron Microscope ◽  
Photoelectron Spectroscopy ◽  
Crystallographic Structure ◽  
X Ray Diffraction ◽  
Facile Synthesis ◽  
X Ray ◽  
Nonwoven Fabrics ◽  
Doped Zno ◽  
Orthogonal Tests ◽  
Scanning Electron

The electroconductive AZO@TiO2whiskers have been successfully preparedviacoating Al doped ZnO onto TiO2whisker. The orthogonal tests were employed to optimize the synthetic conditions. The crystallographic structure and the morphology of the AZO@TiO2whiskers and the polypropylene nonwoven fabrics modified with AZO@TiO2whiskers were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope, four-probe meter, and electrometer. The results showed the AZO@TiO2whiskers exhibited good electroconductive performance. Moreover, the polypropylene nonwoven fabrics modified with AZO@TiO2whiskers revealed excellent antistatic performance indicating wide application of AZO@TiO2whiskers in the antistatic textiles.

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