Synthesis, Structure, Lattice Dynamics and Electrochemistry of Lithiated Manganese Spinel, LiMn2O4

1996 ◽  
Vol 453 ◽  
Author(s):  
C. Julien ◽  
A. Rougier ◽  
G. A. Nazri
Keyword(s):  
Manganese Oxide ◽  
Lattice Dynamics ◽  
Spinel Phase ◽  
Electrochemical Performances ◽  
Voltage Profile ◽  
X Ray Diffraction ◽  
Synthesis Conditions ◽  
Oxide Spinel ◽  
Spinel Manganese Oxide ◽  
Selection Of

AbstractWe report synthesis, crystal structure, lattice dynamics, and electrochemical features of the lithiated manganese oxide spinel prepared through solid state reaction by careful selection of precursors and synthesis conditions. Elemental analysis shows that the material is a lithium-rich spinel phase. X-ray diffraction data and Rietveld refinement indicate formation of a single phase, impurity free, normal spinel of LiMn2O4. Lattice dynamics have been investigated by vibrational spectroscopy and group theoretical analysis has been carried out. Electrochemical performances of the lithiated spinel manganese oxide have been investigated, and the voltage profile of the cathode during lithium intercalation-deintercalation processes, close to equilibrium, has been obtained. The upper 4-volt plateau provides over 130 mA h/g with an excellent cyclability.

X-ray diffraction and impedance spectroscopy studies of lithium manganese oxide spinel

2006 ◽  
Vol 159 (1) ◽  
pp. 412-419 ◽  
Author(s):  
M. Kopeć ◽  
D. Lisovytskiy ◽  
M. Marzantowicz ◽  
J.R. Dygas ◽  
F. Krok ◽  
...  
Keyword(s):  
Impedance Spectroscopy ◽  
Manganese Oxide ◽  
Lithium Manganese Oxide ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lithium Manganese ◽  
Oxide Spinel ◽  
Lithium Manganese Oxide Spinel ◽  
Spectroscopy Studies

scholarly journals X-ray synchrotron radiation studies of actinide materials

2021 ◽  
Vol 28 (6) ◽  
Author(s):  
Roberto Caciuffo ◽  
Gerard H. Lander
Keyword(s):  
Electronic Structure ◽  
Synchrotron Radiation ◽  
Inelastic Scattering ◽  
Lattice Dynamics ◽  
Magnetic Circular Dichroism ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Scattering ◽  
Synchrotron Radiation Techniques ◽  
Selection Of

By reviewing a selection of X-ray diffraction (XRD), resonant X-ray scattering (RXS), X-ray magnetic circular dichroism (XMCD), resonant and non-resonant inelastic scattering (RIXS, NIXS), and dispersive inelastic scattering (IXS) experiments, the potential of synchrotron radiation techniques in studying lattice and electronic structure, hybridization effects, multipolar order and lattice dynamics in actinide materials is demonstrated.

Synthesis, Characterization, and Electrochemical Performances of Substituted Layered Transition Metal Oxides. LiM1-yM'yO2. (M=Ni and Co. M'= B and AI)

1996 ◽  
Vol 453 ◽  
Author(s):  
G. A. Nazri ◽  
A. Rougier ◽  
K. F. Kia
Keyword(s):  
Transition Metal Oxides ◽  
Solubility Limit ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
X Ray ◽  
Long Cycle Life ◽  
Line Intensities ◽  
Treatment Conditions ◽  
Layered Transition Metal ◽  
Selection Of

AbstractThe synthesis, characterization and electrochemical performances of lithiated nickelate and cobaltate doped with Al and B are reported. The synthesis involves solid state reaction between lithium hydroxide, nickel or cobalt oxides and several sources of aluminum and boron. Careful selection of precursors and heat treatment conditions are required to prepare single phase impurity free samples. X-ray diffraction and Rietveld refinement analysis indicate that the layered structure is preserved upon considerable substitution of aluminum and boron. X-ray diffraction line intensities and positions remained in good agreement with the space group. The IR spectra of the samples indicate formation of compressed CoO6 and NiO6, and elongated LiO6 octahedra. The IR vibrational mode of the LiO6 remains in the 200–300 cm-1 and the vibrational modes of the MO6 expand over 400–650 cm-1. Results of long charge-discharge cycling of the samples as cathode materials in lithium cells showed long cycle life. The capacity of the electrodes upon substitution were reduced almost linearly as the concentration of substitution was increased. The solubility limit for the formation of solid solutions upon substitution of Al and B in LiNiO2 and LiCoO2 was found to be around 25%. Specific capacities of the samples were between 120 to 160 mAh/g depending on the amount of substitution.

Synthesis, Structures, and Physical Properties of Yttrium-Doped Strontium Manganese Oxide Films

2002 ◽  
Vol 718 ◽  
Author(s):  
Andrew J. Francis ◽  
Paul A. Salvador
Keyword(s):  
Thin Films ◽  
Manganese Oxide ◽  
Alkaline Earth ◽  
Epitaxial Thin Films ◽  
X Ray Diffraction ◽  
Metal Insulator ◽  
X Ray ◽  
Synthesis Conditions ◽  
Colossal Magnetoresistive

AbstractCubic strontium manganese oxide is an end-member of the colossal magnetoresistive (CMR) family of manganese-based perovskites, Ln1-xAExMnO3. Because normal synthesis conditions lead to the 4-H hexagonal polymorph, high-pressure conditions are typically used to obtain the cubic perovskite polymorph. In this work, we describe the synthesis and structural/physical characterization of the cubic perovskite form of the high-alkaline-earth containing phases of Y1-xSrxMnO3 (x ≥ 0.7) as epitaxial thin films. Thin films of various stoichiometries were grown on single-crystal perovskite substrates SrTiO3, NdGaO3, and LaAlO3 using pulsed laser deposition. After optimizing deposition conditions, the perovskite polymorph is obtained using PLD at 800°C and 10-100 mTorr O2 for x=1, 0.9, 0.8, and 0.7, as demonstrated by x-ray diffraction. Epitaxial growth was determined to be cube-on-cube. Electrical property measurements demonstrated insulating behavior and no metal-insulator transition or magnetoresistive behavior, similar to related stable compounds.

Optimization of the Synthesis Conditions of LiMnPO4 for Lithium Secondary Battery by Solid State Method

2012 ◽  
Vol 602-604 ◽  
pp. 1044-1049 ◽  
Author(s):  
You Rong Wang ◽  
Han Tao Liao ◽  
Jia Wang ◽  
Yu Chan Zhu ◽  
Si Qing Cheng
Keyword(s):  
Solid State ◽  
Electrochemical Properties ◽  
Cycling Performance ◽  
Molar Ratio ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Solid State Method ◽  
Synthesis Conditions ◽  
State Method

In order to enhance the electrochemical performance of LiMnPO4 cathode material, we optimized the synthesis conditions of LiMnPO4 using a simple solid state reaction. The influence of factors of the pre-sintering temperature, carbon source and molar ratio of Zn to Mn, as well as the electrochemical properties of obtained LiMnPO4 powder were studied. The precursor of Zn-doping LiMnPO4/C was characterized by Differential Scanning Calorimetry and thermogravimetry. The microstructure of the samples was characterized by X-ray diffraction (XRD). The optimized LiMnPO4 cathode has good electrochemical properties and its discharge capacity could reach 140.2 mAh g−1 at 0.02 C rate and 111.3 mAh g−1 at 0.1 C rate with satisfactory cycling performance. It implies that the synthesis of LiMnPO4/C composite with excellent electrochemical performances can be achieved by a simple solid state method, which will boost the practical application of LiMnPO4 cathode materials.

IMPROVEMENT ON THE ELECTROCHEMICAL PROPERTIES OF LiMn2O4 BY CODOPING

2010 ◽  
Vol 03 (03) ◽  
pp. 189-191 ◽  
Author(s):  
JUN-FANG WANG ◽  
HAI-LANG ZHANG
Keyword(s):  
Cathode Materials ◽  
Spinel Phase ◽  
Sol Gel ◽  
Lithium Ion ◽  
Cycling Performance ◽  
Constant Current ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
Specific Discharge ◽  
The Stability

The cathode materials Li 1.05 Cr x Mn 1.95-x O 4(x = 0, 0.05, 0.10) for lithium ion batteries were synthesized by sol–gel method and calcined at 650, 700 and 750°C, respectively. The synthesized materials were characterized with X-ray diffraction (XRD). The electrochemical performances of the materials were tested by constant-current cyclic testing at room temperature for 38 cycles. The XRD results showed that the samples of cathode materials synthesized by the method possessed pure spinel phase. The Li1.05Cr0.1Mn1.85O4 powder with better cyclic performance of initial specific discharge capacity of 113.7 mAh ⋅ g-1 can be obtained at the calcination temperature of 700°C for 12 h, with an capacity retention of 95.5% after 38 cycles. It was evident that codoping of Li+ and Cr3+ can improve the stability of spinel structure and cycling performance.

Accelerating the optimization of enzyme-catalyzed synthesis conditions via machine learning and reactivity descriptors

2021 ◽  
Author(s):  
Zhongyu Wan ◽  
Quan-De Wang ◽  
Dongchang Liu ◽  
Jinhu Liang
Keyword(s):  
Machine Learning ◽  
Optimal Synthesis ◽  
Human Knowledge ◽  
Crucial Importance ◽  
Reactivity Descriptors ◽  
Synthesis Conditions ◽  
Wide Range ◽  
Synthesis Reactions ◽  
Selection Of

Enzyme-catalyzed synthesis reactions are of crucial importance for a wide range of applications. An accurate and rapid selection of optimal synthesis conditions is crucial and challenging for both human knowledge...

Sign in / Sign up

Export Citation Format

Share Document