A Novel Method for the Synthesis of Manganese Oxide Nanostructures in a Microemulsion

2011 ◽  
Vol 181-182 ◽  
pp. 485-488 ◽  
Author(s):  
Hua Tian ◽  
Jun Hui He ◽  
Lin Lin Liu
Keyword(s):  
Manganese Oxide ◽  
Manganese Oxides ◽  
Sodium Dodecyl ◽  
Weight Ratio ◽  
Microemulsion System ◽  
X Ray Diffraction ◽  
Oxide Nanostructures ◽  
Transmission Electron ◽  
Novel Method ◽  
Higher Temperature

Microporous manganese oxide in the form of laminar octahedral compounds (birnessite) has been synthesized facilely in a microemulsion system consisting of benzyl alcohol (BA), sodium dodecyl sulfate (SDS) and water. BA also served as a reducing reagent in the formation of manganese oxides. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and Braunauer-Emmett-Teller (BET) measurements. The experimental results indicated that the reaction duration, temperature, and weight ratio of BA/SDS/H2O played key roles in determining the final morophologies of manganese oxide nanomaterials and also in their crystalline phase. Lower process temperature, shorter reaction time and lower BA ratio in the microemulsion were favorable for the formation of birnessite single phase. Mn3O4 nanocrystals appeared at a relatively higher temperature and more BA amount.

Controllable synthesis, characterization, and electrochemical properties of manganese oxide nanoarchitectures

2008 ◽  
Vol 23 (3) ◽  
pp. 780-789 ◽  
Author(s):  
Lichun Zhang ◽  
Liping Kang ◽  
Hao Lv ◽  
Zhikui Su ◽  
Kenta Ooi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrochemical Properties ◽  
Manganese Oxide ◽  
Manganese Oxides ◽  
Hydrothermal Reaction ◽  
Reaction Times ◽  
X Ray Diffraction ◽  
Hydrothermal Conditions ◽  
Hydrothermal Temperature ◽  
Transmission Electron

Flowerlike manganese oxide microspheres and cryptomelane-type manganese oxide nanobelts were selectively synthesized by a simple decomposition of KMnO4 under mild hydrothermal conditions without using template or cross-linking reagents. The effect of varying the hydrothermal times and temperatures on the nanostructure, morphology, compositional, and electrochemical properties of the obtained manganese oxides was investigated. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) studies showed that the flowerlike manganese oxide microspheres could be obtained at relatively low hydrothermal temperatures, while high hydrothermal temperatures were favorable for the formation of cryptomelane-type manganese oxide nanobelts. A morphology and crystalline evolution of the nanostructures was observed as the hydrothermal temperature was increased from 180 to 240 °C. On the basis of changing the temperatures and hydrothermal reaction times, the formation mechanism of cryptomelane-type manganese oxide nanobelts is discussed. Cyclic voltammetry (CV) was used to evaluate the electrochemical properties of the obtained manganese oxide nanostructures, and the results show that the electrochemical properties depend on their shape and crystalline structure. This easily controllable, template-free, and environmentally friendly method has the potential for being used in syntheses of manganese oxide nanomaterials with uniform morphologies and crystal structures.

Characterization of Layered Double Hydroxide Modified with Sodium Dodecyl Sulfate and its Dispersion in Polyethylene

2013 ◽  
Vol 591 ◽  
pp. 138-141
Author(s):  
Zhi Dong Han ◽  
Xin Ke Zhang ◽  
Yue Wang ◽  
Zheng Quan Jiang ◽  
Peng Wang
Keyword(s):  
Sodium Dodecyl Sulfate ◽  
Layered Double Hydroxide ◽  
Sodium Dodecyl ◽  
Melt Blending ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Dodecyl Sulfate ◽  
The Matrix ◽  
Mixing Method ◽  
Double Hydroxide

Mg-Al layered double hydroxide (LDH) was modified with sodium dodecyl sulfate (SDS) by regeneration method. The structure of modified LDH (SDS-LDH) was investigated by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). The composites of SDS-LDH and polyethylene (PE) were prepared by melt blending and solution mixing method with maleated PE (PEgMA) as compatibilizer. The structure of the composites and the dispersion of SDS-LDH in the matrix were investigated by XRD and transmission electron microscopy (TEM), respectively. The results reveal that SDS was successfully intercalated into the interlayer space of LDH. SDS-LDH was hardly exfoliated in PE/PEgMA by melt blending. The nanocomposites of PE/(PEgMA/SDS-LDH) were successfully prepared by melt blending PE with SDS-LDH/PEgMA master-batch obtained by solution mixing. Homogeneous dispersion of SDS-LDH in the matrix was observed by TEM.

An expeditious one-pot synthesis of pyrido[2,3-d]pyrimidines using Fe3O4–ZnO–NH2–PW12O40 nanocatalyst

2019 ◽  
Vol 43 (3-4) ◽  
pp. 135-139
Author(s):  
Pegah Farokhian ◽  
Manouchehr Mamaghani ◽  
Nosrat Ollah Mahmoodi ◽  
Khalil Tabatabaeian ◽  
Abdollah Fallah Shojaie
Keyword(s):  
Electron Microscopy ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Facile Synthesis ◽  
Pyrimidine Derivatives ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Novel Method ◽  
Operational Simplicity

An efficient protocol for the facile synthesis of a series of pyrido[2,3- d]pyrimidine derivatives has been developed applying Fe3O4–ZnO–NH2–PW12O40 nanocatalyst in water. This novel method has the benefits of operational simplicity, green aspects by avoiding toxic solvents and high to excellent yields of products. Fe3O4–ZnO–NH2–PW12O40 was synthesized and characterized by Fourier transform infrared, X-ray diffraction, vibrating sample magnetometer, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and transmission electron microscopy analyses. The nanocatalyst is readily isolated and recovered from the reaction mixture by an external magnet.

Effect of Aging Treatment on Damping Capacity in Mncunife Alloy

2012 ◽  
Vol 246-247 ◽  
pp. 1158-1162
Author(s):  
Xu Fu ◽  
Ning Li ◽  
Yu Hua Wen ◽  
Jing Teng ◽  
Ying Zhang
Keyword(s):  
Electron Microscope ◽  
Aging Treatment ◽  
Damping Capacity ◽  
Torsion Pendulum ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Higher Temperature ◽  
Lower Temperature ◽  
The Relationship

M2052 alloys with various aging treatments are obtained in order to investigate the relationship between aging treatment and damping capacity by the torsion pendulum, X-Ray Diffraction (XRD) and Transmission Electron Microscope (TEM) methods. The results show that M2052 can obtain high damping capacity (δ>0.2) when aged at a range from 400°C to 450°C, and the damping capacity after aged at a lower temperature is higher than that aged at a higher temperature for the maximum values. TEM and XRD results show that fcc-fct transformation occurs after aging treatment. The volumes of fct structures are one of reason to affect the damping capacity in M2052 alloy. The better understanding aging treatment could promote the applications of M2052 alloy.

Direct Preparation of Ce0.8Sm0.2O1.9 Powders Oxidized With H2O2 for Low Temperature SOFCs Application

2005 ◽  
Author(s):  
Jianbing Huang ◽  
Zongqiang Mao ◽  
Bin Zhu ◽  
Lizhai Yang ◽  
Ranran Peng ◽  
...  
Keyword(s):  
Single Phase ◽  
Fluorite Structure ◽  
X Ray Diffraction ◽  
Composite Electrolyte ◽  
Xrd Pattern ◽  
Transmission Electron ◽  
Direct Preparation ◽  
Novel Method ◽  
Power Densities

A novel method was developed to prepare fine doped ceria (DCO) powders directly. Ceria doped with 20 mol. % of samarium (Ce0.8Sm0.2O1.9, SDC) was prepared by in-situ oxidization of hydroxide precipitates with H2O2 in the solutions. The resultant powder desiccated at 85°C overnight was characterized by X-ray diffraction (XRD), thermogravimetry /differential thermal analysis (TG/DTA), and transmission electron microscopy (TEM). The XRD pattern showed that the as-dried SDC powder is single phase with a cubic fluorite structure like that of pure CeO2. An anode-supported SOFC was also fabricated based on SDC and 20wt. % (62mol. %Li2CO3–38 mol. %K2CO3) composite electrolyte, LiNiO2 as cathode and NiO as anode, by cold pressing. Using hydrogen as the fuel and air as the oxidant, the I-V and I-P characteristics exhibit excellent performances and the maximum power densities are about 696, 469, 377 and 240 mWcm−2 at 650, 600, 550 and 500°C, respectively.

scholarly journals Development of a Novel Method for the Fabrication of Nanostructured Zr(x)Ni(y) Catalyst to Enhance the Desorption Properties of MgH2

Catalysts ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 849
Author(s):  
Gracia Shokano ◽  
Zahir Dehouche ◽  
Basile Galey ◽  
Georgeta Postole
Keyword(s):  
Hydrogen Desorption ◽  
Milling Process ◽  
Hydrogen Release ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Electron Microscope Analysis ◽  
Novel Method ◽  
Temperature Programmed ◽  
The Impact

The present work involves the development of a novel method for the fabrication of zirconium nickel (Zr(x)Ni(y)) alloy used as a nanocatalyst to improve the hydrogen storage properties of the Mg/MgH2 system. The catalyst was fabricated through the high-pressure reactor and activated under hydrogen prior to being mechanically milled with the MgH2 for 5 h under argon. The microstructure characterisation of the samples was determined via SEM-EDX (scanning electron microscope analysis–energy dispersive X-ray spectroscopy), XRD (X-ray diffraction) and FE-HRTEM (field emission high resolution transmission electron microscopy), and the desorption characteristic of the nanocomposite (10 wt.% Zr(x)Ni(y)–MgH2) was determined via TPD (temperature-programmed desorption). The nanostructured MgH2 powder milled with 10 wt.% of the activated Zr(x)Ni(y) based nanocatalyst resulted in a faster hydrogen release—5.9 H2-wt.% at onset temperature 210 °C/peak temperature 232 °C. The observed significant improvement in the hydrogen desorption properties was likely to be the result of the impact of the highly dispersed catalyst on the surface of the Mg/MgH2 system, the reduction in particle size during the ball milling process and/or the formation of Mg0.996Zr0.004 phase during the milling process.

Synthesis and Characterization of Ag-PILC Through the Formation of Ag@Montmorillonite Nanocomposite

NANO ◽  
2015 ◽  
Vol 10 (02) ◽  
pp. 1550031 ◽  
Author(s):  
Feng Rao ◽  
Shaoxian Song ◽  
Alejandro Lopez-Valdivieso
Keyword(s):  
Ag Nanoparticles ◽  
Silver Ions ◽  
Trisodium Citrate ◽  
X Ray Diffraction ◽  
Exchange Method ◽  
Ph Values ◽  
Transmission Electron ◽  
Bet Method ◽  
Novel Method

Ag pillared interlayered clays ( Ag -PILCs) were synthesized through a novel method, in which Ag nanoparticles were formed in montmorillonite interlayers. In this method, silver ions were first exchanged into montmorillonite interlayers, and then reduced into Ag nanoparticles by trisodium citrate at 100°C in aqueous solutions. The synthesized Ag @montmorillonite nanocomposite was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM), and its surface area was evaluated by using Brunauer–Emmet–Teller (BET) method. Compared to traditional PILCs synthesized through ion exchange method, the formed Ag -PILCs had better thermal stability and stronger structure because their pillars are nanoparticles. Furthermore, this method introduces a possibility to control the size of the pillars and thus the pore size of the PILCs, due to that the nanoparticle pillars can be modified on their forms and diameters in the synthesizing process. Also, it was found that the intercalating Ag nanoparticle pillars were formed at restricted pH values and silver ion concentrations.

Clay minerals in hydrothermally altered basalts from Middle Atlas, Morocco

Clay Minerals ◽  
2005 ◽  
Vol 40 (1) ◽  
pp. 67-77 ◽  
Author(s):  
A. Dekayir ◽  
M. Amouric ◽  
J. Olives
Keyword(s):  
Electron Microscopy ◽  
Clay Minerals ◽  
Crystallization Process ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Equilibrium Conditions ◽  
Transmission Electron ◽  
Middle Atlas ◽  
Higher Temperature ◽  
Main Components

AbstractClay minerals occur as replacements of olivine, pyroxenes, plagioclase and interstitial materials, and as vesicle fillings, in altered basalts from the Middle Atlas (Morocco). Phyllosilicates are the main components of this alteration process. They have been characterized here by optical microscopy, X-ray diffraction, scanning electron microscopy and high-resolution transmission electron microscopy as saponite, talc, corrensite and chlorite. The homogeneity of the chemical compositions of these phyllosilicates, in different alteration environments, probably means that they are controlled by the composition of the hydrothermal fluid. Talc-saponite-corrensite (with dominant saponite) is the clay mineral association most frequently observed (corrensite being more abundant in the vesicular levels of the basalts). Such an association, with no evidence of albite and zeolite, suggests that these basalts have suffered minimal alteration at relatively low temperatures. Another association, chlorite-corrensite, was detected in a deeper (vesicular) sample, probably resulting from a slightly higher temperature. Lastly, only discrete phyllosilicates (i.e. no random mixed-layer minerals) were observed. This suggests that near-equilibrium conditions prevailed during this alteration stage and that a dissolution-crystallization process was the main mechanism of transformation.

H2 Uptake and Synthesis of the Li-dispersed Manganese Oxide Nanotubes

2007 ◽  
Vol 7 (11) ◽  
pp. 4033-4036 ◽  
Author(s):  
Jin Bae Lee ◽  
Soon Chang Lee ◽  
Hae Jin Kim
Keyword(s):  
Electron Microscopy ◽  
Manganese Oxide ◽  
Hydrogen Adsorption ◽  
Gravimetric Method ◽  
Anodic Aluminum Oxide Template ◽  
Outer Diameter ◽  
X Ray Diffraction ◽  
Anodic Aluminum ◽  
Transmission Electron ◽  
Potential Applications

Well aligned Li-dispersed manganese oxide nanotubes were prepared using LiNO3, Mn(NO3)2 · xH2O and an anodic aluminum oxide template by solvent-free method for potential applications in H2 storage. The obtained nanotubes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The analyses revealed the Mn2O3 nanotubes to have a cubic structure with a uniform length, 40–50 nm in wall thickness and 250 ± 10 nm in the outer diameter. The level of H2 adsorption was determined using the gravimetric method. The Li-dispersed manganese oxide nanotubes showed a 0.26 wt% for the amount of hydrogen adsorption at 77 K under 4.5 MPa.

Effect of Calcination Temperature on the Morphological and Phase Structure of Hydrothermally Synthesized Copper Ion Doped TiO2 Nanotubes

2014 ◽  
Vol 1024 ◽  
pp. 7-10 ◽  
Author(s):  
Mohd Hasmizam Razali ◽  
M.N. Ahmad-Fauzi ◽  
Abdul Rahman Mohamed ◽  
Srimala Sreekantan
Keyword(s):  
Calcination Temperature ◽  
Morphological Evolution ◽  
Copper Ion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Different Temperatures ◽  
Scanning Electronmicroscopy ◽  
Higher Temperature ◽  
Uniform Diameter

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).

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