Phase-Controllable Synthesis of Nickel Phosphides Using a New Ligand Myristic Acid

2013 ◽  
Vol 679 ◽  
pp. 23-26 ◽  
Author(s):  
Jie Chang ◽  
Yan Hui Ning ◽  
Su Li Wu ◽  
Shu Fen Zhang

Myristic acid was employed as a new ligand in a facile hydrothermal method to synthesize nanosized nickel phosphide particles with controlled phases at different temperatures. The phases of the as-obtained products were determined by X-ray powder diffraction (XRD) patterns. The morphologies of the products were characterized by transmission electron microscopy (TEM). Experiments indicated that pure Ni2P phase could be prepared at 160°C for 10h when nontoxic red phosphorus and nickel dichloride were used as starting materials in the presence of myristic acid. While pure Ni12P5 phase could be prepared by increasing the reaction temperature to 200°C.

2014 ◽  
Vol 631 ◽  
pp. 193-197
Author(s):  
A.M. Escamilla-Pérez ◽  
D.A. Cortés-Hernández ◽  
J.M. Almanza-Robles ◽  
D. Mantovani ◽  
P. Chevallier

Powders of Mg0.4Ca0.6Fe2O4were prepared by sol-gel using ethylene glycol and Mg, Ca and Fe nitrates as starting materials. Those powders were heat treated at different temperatures (300, 400, 500 and 600 °C) for 30 min. The materials obtained were characterized by X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The Ca-Mg ferrite with the most appropriate magnetic properties was further analyzed by transmission electron microscopy (TEM). The heating capability of the nanoferrites was also tested via magnetic induction. The XRD patterns of these Ca-Mg ferrites showed a cubic inverse spinel structure. Furthermore, neither traces of hematite nor orthorhombic Ca ferrite phases were detected. Moreover, all the Ca-Mg ferrites are superparamagnetic and the particle size distribution of these Ca-Mg magnetic nanoparticles exhibits an average diameter within the range of 10-14 nm. The needed temperature for hyperthermia treatment was achieved at around 12 min.


Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1298 ◽  
Author(s):  
Muhammad Arif Khan ◽  
Nafarizal Nayan ◽  
Shadiullah Shadiullah ◽  
Mohd Khairul Ahmad ◽  
Chin Fhong Soon

In the present work, a facile one-step hydrothermal synthesis of well-defined stabilized CuO nanopetals and its surface study by advanced nanocharacterization techniques for enhanced optical and catalytic properties has been investigated. Characterization by Transmission electron microscopy (TEM) analysis confirmed existence of high crystalline CuO nanopetals with average length and diameter of 1611.96 nm and 650.50 nm, respectively. The nanopetals are monodispersed with a large surface area, controlled morphology, and demonstrate the nanocrystalline nature with a monoclinic structure. The phase purity of the as-synthesized sample was confirmed by Raman spectroscopy and X-ray diffraction (XRD) patterns. A significantly wide absorption up to 800 nm and increased band gap were observed in CuO nanopetals. The valance band (VB) and conduction band (CB) positions at CuO surface are measured to be of +0.7 and −1.03 eV, respectively, using X-ray photoelectron spectroscopy (XPS), which would be very promising for efficient catalytic properties. Furthermore, the obtained CuO nanopetals in the presence of hydrogen peroxide ( H 2 O 2 ) achieved excellent catalytic activities for degradation of methylene blue (MB) under dark, with degradation rate > 99% after 90 min, which is significantly higher than reported in the literature. The enhanced catalytic activity was referred to the controlled morphology of monodispersed CuO nanopetals, co-operative role of H 2 O 2 and energy band structure. This work contributes to a new approach for extensive application opportunities in environmental improvement.


1994 ◽  
Vol 9 (1) ◽  
pp. 229-235 ◽  
Author(s):  
Ch. Laurent ◽  
J.J. Demai ◽  
A. Rousset ◽  
K.R. Kannan ◽  
C.N.R. Rao

Fe-Cr/Al2O3 metal-ceramic composites prepared by hydrogen reduction at different temperatures and for different periods have been investigated by a combined use of Mössbauer spectroscopy, x-ray diffraction, transmission electron microscopy, and energy-dispersive x-ray spectroscopy in order to obtain information on the nature of the metallic species formed. Total reduction of Fe3+ does not occur by increasing the reduction time at 1320 K from 1 to 30 h, and the amount of superparamagnetic metallic species is essentially constant (about 10%). Temperatures higher than 1470 K are needed to achieve nearly total reduction of substitutional Fe3+. Interestingly, iron favors the reduction of chromium. The composition of the Fe-Cr particles is strongly dependent on their size, the Cr content being higher in particles smaller than 10 nm.


2011 ◽  
Vol 412 ◽  
pp. 263-266
Author(s):  
Hong Wei Zhang ◽  
Li Li Zhang ◽  
Feng Rui Zhai ◽  
Jia Jin Tian ◽  
Can Bang Zhang

The higher mechanical strength of Al87Ce3Ni8.5Mn1.5 nanophase amorphous composites has been obtained with two methods. The first nanophase amorphous composites are directly produced by the single roller spin quenching technology. The method taken for the second nanophase amorphous composites is at first to obtain amorphous single-phase alloy, followed by annealed at different temperatures .The formative condition, the microstructure, the particle size, the volume fraction of α-Al phase and microhardness of nanophase amorphous composites etc have been investigated and compared by X-ray diffraction (XRD) and transmission electron microscopy (TEM) and differential scanning calorimetry (DSC). The microstructure of composites produced by the second method is higher than the former, the fabricated material structure of the system is more uniform and the process is easier to control.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Changyu Li ◽  
Shouxin Liu

Mesoporous nanosheets of single-crystallineβ-nickel hydroxide (β-Ni(OH)2) were successfully synthesized via a facile hydrothermal method using Ni(NO3)2 · 6H2O as precursor in a mixed solution of sodium hydroxide (NaOH) and sodium dodecylbenzenesulfonate (SDBS). Single-crystalline nickel oxide (NiO) mesoporous nanosheets can be obtained through a thermal decomposition method usingβ-Ni(OH)2mesoporous nanosheets as precursor. The influences of SDBS and hydrothermal treatment were carefully investigated; the results showed that they played important roles in the formation ofβ-Ni(OH)2mesoporous nanosheets. The as-obtainedβ-Ni(OH)2and NiO were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravity-differential thermal analysis (TG-DTA), and specific surface area, and pore size test.


Clay Minerals ◽  
1985 ◽  
Vol 20 (1) ◽  
pp. 115-124 ◽  
Author(s):  
K. P. Tomar

AbstractThe mineralogy of the fine clay fraction (<0·2 μm) of two soil pedons (Aquic and Udic Haplustalfs) representing the wheat-sugarcane belt of the Indo-Gangetic alluvial plain was studied by X-ray diffraction, differential thermal analysis, transmission electron microscopy, and by chemical analysis. The XRD patterns are characterized by unusually high spacings which are interpreted in terms of an interstratification comprising smectite, illite and ‘chlorite’ components. The CEC data (Ca/Mg and K/NH4) also indicate the possible presence of vermiculite. A plateau bridging the 7–10 Å maxima in K-saturated specimens heated at 300°C suggests interstratification of kaolinite and smectite, although this may not be part of the above interstratification. The diffuse bands shown by Mg-glycerol-solvated Ap-horizon clays at ∼21 Å, and the increasing elimination of XRD peaks in the > 10 Å region with distance from the surface, suggests that the expanding layers have a slight tendency to segregate in Ap horizon samples and that randomization tends to increase with depth. Discrete illite and small amounts of kaolinite were also detected.


2013 ◽  
Vol 826 ◽  
pp. 248-252
Author(s):  
Zheng Xian Ma ◽  
Qiao Ling Liu ◽  
Lan Qin Wang ◽  
Lu Feng Pang

ZnO nanorods were successfully synthesized using ZnCl2 and NaOH as the starting materials without surfactants, template supporting and structure-directing solvent at low temperatures (20 °C 90 °C). X-ray powder diffraction (XRD) and transmission electron microscopy (TEM) were used to analyze the crystal structure and surface morphology. Analysis of XRD patterns showed that ZnO clusters are single hexagonal phases of wurtzite structure with no other impurities. Also, TEM images revealed that the size of a single ZnO nanorod was between 32 and 60 nm in diameter and between 470 and 740 nm in length. Furthermore, the ZnO nanorods exhibited significant Raman spectrum optical properties suggesting that they have potential for opto-electronic application.


2014 ◽  
Vol 1024 ◽  
pp. 7-10 ◽  
Author(s):  
Mohd Hasmizam Razali ◽  
M.N. Ahmad-Fauzi ◽  
Abdul Rahman Mohamed ◽  
Srimala Sreekantan

Morphological evolution and phase transformations of copper ion doped TiO2nanotubes after being calcined at different temperatures were studied by field emission scanning electronmicroscopy, transmission electron microscopy, and X-ray diffraction. After calcination at 300°C, the nanotubes with uniform diameter and length wereobtained. At 400°C, the nanotube structures were maintained. Nevertheless the inner tube diameter became narrower, and in same instances disappeared due to aggregation of nanotubes. The copper ion doped TiO2nanotubes then transformed to nanorodsat 500°C and the length of the nanorodsshortens after calcination at 600 °C. When the calcination temperature was further increased to 700°C, the nanorodsdisintegrate to form nanoparticles. On the other hand the phase structures of copper ion doped TiO2nanotubes calcined at 300 and 400 °C were TiO2hexagonal. After calcined at higher temperature (600 and 700°C) they transformed to anatase TiO2(tetragonal).


2017 ◽  
Vol 889 ◽  
pp. 234-238
Author(s):  
Mohd Hasmizam Razali ◽  
Nur Arifah Ismail ◽  
Mahani Yusoff

Pure and F doped TiO2 nanotubes was synthesized using simple hydrothermal method. The hydrothermal was conducted using teflon-liner autoclave and maintained at 150oC for 24 hours. The characterization of synthesised product was carried out using x-ray diffraction (XRD), transmission electron microscope (TEM), energy dispersive of x-ray spectroscopy (EDX) and ultra violet – visible light diffuse reflectance spectroscopy (UV-Vis DRS) for band gap measurements. XRD patterns indicated that anatase TiO2 phase was remained after F doping suggested that fluorine was highly dispersed into TiO2 by substituted with O in the TiO2 lattice to formed TiO2-xFx solid solution. Morphology investigation using TEM found out small diameter of nanotubes structure within 8 – 10 nm of pure and F doped TiO2 nanotubes. The band gap energy (Eg) of both nanotubes samples were almost similar proposing that F doping does not modify the band gap energy.


2013 ◽  
Vol 275-277 ◽  
pp. 1733-1736 ◽  
Author(s):  
Zi Tao Yang ◽  
Bo Wen Cheng ◽  
Yong Nan Zhao

NiFe2O4 nanoparticles was successfully synthesized by hydrothermal decomposition of a gel of Ni-Fe-EG (EG=ethylene glycol) in water solution. The crystal structure and morphologies of the products were characterized by X-ray diffraction (XRD) and Transmission electron microscopy (TEM). All the diffraction peaks in XRD patterns revealed that the as-synthesized nanoparticles were pure NiFe2O4. TEM images disclosed that the particle sizes of the nanoparticles were in the range of 10 − 25nm. The cyclic voltammetry (CV) and galvanostatic charge/discharge results tested in 6M KOH solution revealed a double layer capacitive behavior and a revisable charge/discharge property.


Sign in / Sign up

Export Citation Format

Share Document