The Preparation and Characterization of LiFe0.98Ni0.01Nb0.01PO4/C by Carbon Reduction Route

2012 ◽  
Vol 581-582 ◽  
pp. 570-573
Author(s):  
Jia Feng Zhang ◽  
Bao Zhang ◽  
Xue Yi Guo ◽  
Jian Long Wang ◽  
He Zhang Chen ◽  
...  
Keyword(s):  
Carbon Coating ◽  
Xrd Analysis ◽  
Initial Discharge Capacity ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
X Ray ◽  
Carbon Reduction ◽  
Initial Discharge ◽  
Structure Morphology

The LiFe0.98Ni0.01Nb0.01PO4/C was synthesized by carbon reduction route using FePO4•2H2O as precursor. The LiFe0.98Ni0.01Nb0.01PO4/C sample was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and electrochemical measurements. The XRD analysis, SEM and TEM images show that sample has the good crystal structure, morphology and carbon coating. The charge-discharge tests demonstrate that the powder has the better electrochemical properties, with an initial discharge capacity of 164.6 mAh•g−1 at current density of 0.1 C. The capacity retention reaches 99.8% after 100 cycles at 0.1C.

Synthesis and Characterization of Ramsdellite Type Lithium Titanate Anode Materials by Spray Pyrolysis

2013 ◽  
Vol 566 ◽  
pp. 127-130
Author(s):  
Hiroshi Kawaguchi ◽  
Takayuki Kodera ◽  
Takashi Ogihara
Keyword(s):  
Spray Pyrolysis ◽  
Discharge Capacity ◽  
Anode Materials ◽  
Lithium Titanate ◽  
Initial Discharge Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Initial Discharge ◽  
Precursor Powders

Spherical Li2Ti3O7precursor powders were successfully prepared by spray pyrolysis. X-ray diffraction analysis revealed that the ramsdellite phase was obtained by calcining at 1100 °C for 3 h under an argon/hydrogen (95/5 %) atmosphere. The Li2Ti3O7anode exhibited higher rechargeable capacity and excellent cycle stability. The rechargeable capacity of the Li2Ti3O7anode was approximately 168 mAh/g at 0.1 C. The discharge capacity of the Li2Ti3O7anode after 100 cycles was approximately 90% of the initial discharge capacity.

Synthesis and Electrochemical Performance of Li3V2(PO4)3 Cathode Material by Microwave Method

2012 ◽  
Vol 490-495 ◽  
pp. 3624-3627
Author(s):  
Sheng Kui Zhong ◽  
Hui Ping Hu ◽  
Jie Qun Liu
Keyword(s):  
Perfect Crystal ◽  
Microwave Method ◽  
Initial Discharge Capacity ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
Voltage Range ◽  
X Ray ◽  
Initial Discharge ◽  
Charge Discharge ◽  
Discharge Test

Monoclinic Li3V2(PO4)3 was synthesized by a microwave method. The influence of sintering temperatures and time on the synthesis of Li3V2(PO4)3 was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and charge-discharge test. The results of these tests shows that the Li3V2(PO4)3 sample synthesized at 850 °C for 15 min has pure and perfect crystal. The charge-discharge test shows the Li3V2(PO4)3 sample with optimal synthesis condition has the best initial discharge capacity of 120 mAh/g, with capacity retention of 101 mAh/g after 50 cycles, in the voltage range of 3.0 V–4.2 V.

The Effect of CTAB Additive on Performance of Layered Cathode Material Li0.96Na0.04Ni1/3Co1/3Mn1/3O2

2013 ◽  
Vol 800 ◽  
pp. 501-504
Author(s):  
Chun Xia Gong ◽  
Oluwatosin Emmanued Bankole ◽  
Li Xu Lei
Keyword(s):  
Cathode Material ◽  
Cycle Performance ◽  
Initial Discharge Capacity ◽  
X Ray Diffraction ◽  
Electrochemical Test ◽  
Capacity Retention ◽  
X Ray ◽  
Initial Discharge ◽  
Pure Phase ◽  
Scanning Electron

Li0.96Na0.04Ni1/3Co1/3Mn1/3O2with CTAB as additive was synthesized. X-ray diffraction pattern reveals the product of the material with CTAB is pure phase. Scanning electron microscopy shows that the powders are average of 200 nm. Electrochemical test shows it in terms of high initial discharge capacity (175.6 mAhg-1) and exhibits good cycle performance with the capacity retention of 93.39 % after 90 cycles compared to the material has no additive (167.6 mAhg-1and 71.18 %) at 0.1 C rate. Therefore, CTAB as additive should improve the performance of Li0.96Na0.04Ni1/3Co1/3Mn1/3O2cathode material.

Characterization and A Preliminary Study of TiO2 Synthesis from Lampung Iron Sand

2020 ◽  
Vol 849 ◽  
pp. 113-118
Author(s):  
Yayat Iman Supriyatna ◽  
Slamet Sumardi ◽  
Widi Astuti ◽  
Athessia N. Nainggolan ◽  
Ajeng W. Ismail ◽  
...  
Keyword(s):  
Food Packaging ◽  
Xrd Analysis ◽  
Major Elements ◽  
Raw Material ◽  
Solid Residue ◽  
X Ray Diffraction ◽  
X Ray ◽  
Leaching Solution ◽  
Ti Content

The purpose of this study is to characterize Lampung iron sand and to conduct preliminary experiments on the TiO2 synthesis which can be used for the manufacturing of functional food packaging. The iron sand from South Lampung Regency, Lampung Province that will be utilized as raw material. The experiment was initiated by sieving the iron sand on 80, 100, 150, 200 and 325 mesh sieves. Analysis using X-Ray Fluorescence (XRF) to determine the element content and X-Ray Diffraction (XRD) to observe the mineralization of the iron sand was conducted. The experiment was carried out through the stages of leaching, precipitation, and calcination. Roasting was applied firstly by putting the iron sand into the muffle furnace for 5 hours at a temperature of 700°C. Followed by leaching using HCl for 48 hours and heated at 105°C with a stirring speed of 300 rpm. The leaching solution was filtered with filtrate and solid residue as products. The solid residue was then leached using 10% H2O2 solution. The leached filtrate was heated at 105°C for 40 minutes resulting TiO2 precipitates (powder). Further, the powder was calcined and characterized. Characterization of raw material using XRF shows the major elements of Fe, Ti, Mg, Si, Al and Ca. The highest Ti content is found in mesh 200 with 9.6%, while iron content is about 80.7%. While from the XRD analysis, it shows five mineral types namely magnetite (Fe3O4), Rhodonite (Mn, Fe, Mg, Ca) SiO3, Quart (SiO2), Ilmenite (FeOTiO2) and Rutile (TiO2). The preliminary experiment showed that the Ti content in the synthesized TiO2 powder is 21.2%. The purity of TiO2 is low due to the presence of Fe metal which is dissolved during leaching, so that prior to precipitation purification is needed to remove impurities such as iron and other metals.

Production and Characterization of HVOF Sprayed NiCr-TiC Coatings Using SHS Powder Feedstock

2000 ◽  
Author(s):  
M.T. Blatchford ◽  
A.J. Horlock ◽  
D.G. McCartney ◽  
P.H. Shipway ◽  
J.V. Wood
Keyword(s):  
Thermal Spraying ◽  
Xrd Analysis ◽  
Powder Size ◽  
Coating Properties ◽  
X Ray Diffraction ◽  
Hvof Spraying ◽  
X Ray ◽  
Wear Rates ◽  
Powder Feedstock

Abstract In this paper, the production of NiCr-TiC powder by SHS, suitable for HVOF spraying, is discussed together with results on the microstructure and coating properties. Compacts for SHS were prepared by mixing elemental Ti and C with pre-alloyed Ni-20wt.% Cr powder to give an overall composition of 35wt.% NiCr and 65wt.% TiC. These were then ignited and a self-sustaining reaction proceeded to completion. Reacted compacts were crushed, sieved, and classified to give feedstock powders in size ranges of 10-45 µm and 45-75 µm. All powder was characterized prior to spraying based on particle size distribution, x-ray diffraction (XRD), and scanning electron microscopy (SEM/EDS). Thermal spraying was performed using both H2 and C3H6 as fuel gases in a UTP/Miller Thermal HVOF system. The resulting coatings were characterized by SEM and XRD analysis, and the microstructures correlated with powder size and spray conditions. Abrasive wear was determined by a modified 'dry sand rubber wheel' (DSRW) test and wear rates were measured. It has been found that wear rates comparable to those of HVOF sprayed WC-17wt% Co coatings can be achieved.

Effect of Synthesis Temperature on Structure and Electrochemical Properties of Nano-Sized Li4Ti5O12 by Self-Combustion Method

2011 ◽  
Vol 399-401 ◽  
pp. 1487-1490
Author(s):  
Zhi Yong Yu ◽  
Han Xing Liu
Keyword(s):  
Electrochemical Properties ◽  
Combustion Method ◽  
Synthesis Temperature ◽  
Electrochemical Analysis ◽  
Initial Discharge Capacity ◽  
X Ray Diffraction ◽  
Spinel Type ◽  
X Ray ◽  
Initial Discharge ◽  
Pure Phase

The spinel-type Li4Ti5O12 cathode materials were synthesized by a self-combustion method. The effects of synthesis temperature on the structural and electrochemical properties of the Li4Ti5O12 were investigated. The prepared samples were characterized by X-ray diffraction (XRD), SEM, TEM and electrochemical analysis. The results revealed that pure phase and well-crystallized Li4Ti5O12 with nano-sized could be synthesized at a calcination temperature of 750°C. The sample prepared under the condition had the highest initial discharge capacity of 164 mAh/g and shown good capacity rentention during 50 cycles between 1.0-2.5V at 0.1C.

Microstructural Characterization of Glass-to-Metal Brazed Joint

2012 ◽  
Vol 616-618 ◽  
pp. 1732-1735 ◽  
Author(s):  
Xi Hai Shen ◽  
Yu Gang Zheng ◽  
Liang Chang ◽  
Jin Jia Guo ◽  
Song Bin Ye ◽  
...  
Keyword(s):  
Thermal Power ◽  
Microstructural Characterization ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solar Thermal Power ◽  
Brazed Joints ◽  
Brazed Joint ◽  
Scanning Electron

Aiming at the glass-to-metal seals serving in the Solar Thermal Power (STP), glass-to-metal vacuum brazed joints were studied. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were performed to examine the microstructure and element contents of interface seam on the glass-to-metal vacuum brazed joints. Also, the compositional concentration of the interface seam was measured by using energy dispersive spectroscopy (EDS).

Preparation and Characterization of Ce-Doped Ba0.2Sr0.8TiO3 Ferroelectric Ceramics

2010 ◽  
Vol 97-101 ◽  
pp. 1091-1096
Author(s):  
Dong Fang Han ◽  
Qun Tang ◽  
Qing Meng Zhang ◽  
Lei Wang ◽  
Ju Du
Keyword(s):  
Dielectric Constant ◽  
Xrd Analysis ◽  
Ferroelectric Ceramics ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure And Property ◽  
Dielectric Constant And Loss ◽  
Ce Content ◽  
Doping Ratio

The structure and property of Ce-doped Ba0.2Sr0.8TiO3 (BST) were investigated as a function of Ce content. The density experiment results confirmed that increasing the Ce doping ratio caused the decrease in shrinkage factor of BST in the sintering procedure. Additionally, both Scanning Electron Microscope (SEM) and X-ray diffraction (XRD) analysis showed that the grain size of Ce-doped BST was dependent on the Ce content. Further more, the dielectric constant and dielectric loss had a curve relationship with increasing Ce content. The improvement of the electrical properties of Ce doping BST may be related to the decrease in the concentration of oxygen vacancies. According to the research, the diameter of grain, the dielectric constant and loss factor of the 1mol% Ce-doped Ba0.2Sr0.8TiO3 were 500nm, 365.8 and 0.0063, respectively.

Preparation of LiFePO4/C Composite Powders

2011 ◽  
Vol 391-392 ◽  
pp. 377-380
Author(s):  
Guo Jun Li ◽  
Ming Yang ◽  
Hai Li Jing ◽  
Rui Ming Ren
Keyword(s):  
Citric Acid ◽  
Oxalic Acid ◽  
Specific Capacity ◽  
Xrd Analysis ◽  
X Ray Diffraction ◽  
Composite Powders ◽  
Charge Capacity ◽  
X Ray ◽  
Initial Charge

LiFePO4/C composite powders were prepared by a simple reaction of as-synthesized FePO4•2H2O, LiOH•H2O, oxalic acid and citric acid. The influence of oxalic acid and citric acid in different ratios was investigated on morphology and electrochemical performance of LiFePO4/C composite powders. The characterization of the composites included X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD analysis indicates that the material is well crystallized without impurities. The obtained LiFePO4/C composite powders with well dispersion at CA/OA ratio of 1:1.50 and the initial charge capacity reached 159.3 mAhg-1 at 0.1C rate, meanwhile, the particles prepared at 1:0.75 were close to spherical in shape and the specific capacity value was 149.8 mAhg-1 at 0.1C rate, with a slight decrease on greater C-rates reaching 141.3 mAhg-1 at 1C.

Synthesis and Characterization of Li0.97K0.03FePO4/Graphene Composites by Carbonthermal Reduction Method

2014 ◽  
Vol 687-691 ◽  
pp. 4327-4330
Author(s):  
Yan Wang ◽  
Zhe Sheng Feng ◽  
Lu Lin Wang ◽  
Jin Ju Chen ◽  
Zhen Yu He
Keyword(s):  
Discharge Capacity ◽  
Photoelectron Spectroscopy ◽  
Reduction Method ◽  
Electrochemical Impedance ◽  
Impedance Spectra ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
Electrochemical Impedance Spectra ◽  
X Ray

Li0.97K0.03FePO4 and Li0.97K0.03FePO4/graphene composites were synthesized by carbothermal reduction method using acetylene black as carbon source. The structure and electrochemical properties of the prepared materials were investigated with X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy, galvanostatic charge and discharge and electrochemical impedance spectra tests. The results indicated that K doping improves the cyclic stability of samples, the addition of small amounts of graphene results in better electronic properties on sample. Li0.97K0.03FePO4/graphene showed discharge capacity of 158.06 and 90.55 mAh g-1 at 0.1 C and 10 C, respectively. After the 50 cycle test at different rates, the reversible discharge capacity at 0.1 C was 158.58 mAh g-1, indicating the capacity retention ratio of 100.32%.

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