Enabling Anionic Redox Stability of P2‐Na 5/6 Li 1/4 Mn 3/4 O 2 by Mg Substitution

2021 ◽  
pp. 2105404
Author(s):  
Yangyang Huang ◽  
Yongcheng Zhu ◽  
Anmin Nie ◽  
Haoyu Fu ◽  
Zhiwei Hu ◽  
...  
Keyword(s):  
Redox Stability ◽  
Mg Substitution

The Solid Solutions Gd2Cu2In1–xMgx – Drastic Increase of the Curie Temperature upon In/Mg Substitution

2010 ◽  
Vol 65 (12) ◽  
pp. 1516-1520 ◽  
Author(s):  
Wilfried Hermes ◽  
Falko M. Schappacher ◽  
Rainer Pöttgen
Keyword(s):  
Curie Temperature ◽  
Intermetallic Compounds ◽  
Solid Solutions ◽  
Temperature Increase ◽  
Magnesium Content ◽  
Lattice Parameter ◽  
Weiss Constant ◽  
Drastic Increase ◽  
Complete Set ◽  
Mg Substitution

The Mo2B2Fe-type intermetallic compounds Gd2Cu2In and Gd2Cu2Mg form a complete set of solid solutions Gd2Cu2In1−xMgx. The a lattice parameter, the Weiss constant and the Curie temperature increase with increasing magnesium content in an almost Vegard-like manner, while the c parameter remains almost constant. All members of the solid solutions show ferromagnetism with TCs between 114 and 80 K.

Computational Studies of Magnesium and Strontium Substitution in Hydroxyapatite

2012 ◽  
Vol 529-530 ◽  
pp. 123-128 ◽  
Author(s):  
Flora E. Imrie ◽  
Marta Corno ◽  
Piero Ugliengo ◽  
Iain R. Gibson
Keyword(s):  
Density Functional ◽  
Structural Changes ◽  
Harmonic Approximation ◽  
Site Preference ◽  
Ionic Radii ◽  
Biologically Relevant ◽  
Site Preferences ◽  
Mechanical Approach ◽  
Quantum Mechanical Approach ◽  
Mg Substitution

The properties of hydroxyapatite can be improved by substitution of biologically relevant ions, such as magnesium (Mg) and strontium (Sr), into its structure. Previous work in the literature has not reached agreement as to site preferences in these substitutions, and there are suggestions that these may change with differing levels of substitution. The current work adopted a quantum mechanical approach based on density functional theory using the CRYSTAL09 code to investigate the structural changes relating to, and site preferences of, magnesium and strontium substitution (to 10 mol%) in hydroxyapatites and also to predict the corresponding vibrational spectra in the harmonic approximation. The structures underwent full geometrical optimisation within the P63 space group, indicating an energetic site preference for the Ca (2) site in the case of Mg substitution, and the Ca (1) site in the case of Sr. Shrinkage of the unit cell was observed in the case of Mg substitution, and expansion in the case of Sr substitution, in agreement with the corresponding ionic radii. Thermodynamic properties of the structures obtained from the harmonic vibrational frequency calculations confirmed that the structures were minima on the potential energy surface. Isotopic substitutions indicated that the main contribution of Sr and Mg to vibrational modes is at frequencies < 400 cm-1.

A- and B-site doping effect on physicochemical properties of Sr2−xBaxMMoO6 (M = Mg, Mn, Fe) double perovskites — candidate anode materials for SOFCs

2016 ◽  
Vol 09 (04) ◽  
pp. 1641002 ◽  
Author(s):  
Kun Zheng ◽  
Konrad Świerczek
Keyword(s):  
Physicochemical Properties ◽  
Solid Oxide Fuel Cells ◽  
Anode Materials ◽  
Full Range ◽  
Solid Oxide ◽  
Double Perovskites ◽  
Reducing Conditions ◽  
Redox Stability ◽  
Very High

In this work, we evaluate the physicochemical properties of Sr[Formula: see text]BaxMMoO6 (M [Formula: see text] Mg, Mn, Fe) double perovskites as alternative anode materials for solid oxide fuel cells, for which the effect of substitution of strontium by barium in a full range of compositions is studied. The crystal structure, microstructure, characterization of transport properties (electrical conductivity, Seebeck coefficient) and oxygen content as a function of temperature, as well as chemical stability in oxidizing and reducing conditions are discussed. Fe- and Mo-containing Sr[Formula: see text]BaxFeMoO6 oxides show very high total conductivities with values of 100–1000 S[Formula: see text][Formula: see text]cm[Formula: see text], while Sr[Formula: see text]BaxMgMoO6 present good redox stability.

Influence of Mg-substitution on the physicochemical properties of calcium phosphate powders

2007 ◽  
Vol 42 (6) ◽  
pp. 1040-1050 ◽  
Author(s):  
J. Marchi ◽  
A.C.S. Dantas ◽  
P. Greil ◽  
J.C. Bressiani ◽  
A.H.A. Bressiani ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Physicochemical Properties ◽  
Mg Substitution

Effect of bimetallic (Ca, Mg) substitution on magneto-optical properties of NiFe2O4 nanoparticles

2019 ◽  
Vol 45 (5) ◽  
pp. 6021-6029 ◽  
Author(s):  
Y. Slimani ◽  
M.A. Almessiere ◽  
M. Nawaz ◽  
A. Baykal ◽  
S. Akhtar ◽  
...  
Keyword(s):  
Optical Properties ◽  
Nife2o4 Nanoparticles ◽  
Mg Substitution

Effect of pH on Structural Changes in Perch Hemoglobin that Can Alter Redox Stability and Heme Affinity

2009 ◽  
Vol 18 (4) ◽  
pp. 416-423 ◽  
Author(s):  
Mark P. Richards ◽  
Roman Aranda ◽  
Cai He ◽  
George N. Phillips
Keyword(s):  
Structural Changes ◽  
Effect Of Ph ◽  
Redox Stability

Early- and Late-Lanthanide Pyridinethiolates:  Synthesis, Redox Stability, and Structure

1997 ◽  
Vol 36 (25) ◽  
pp. 5772-5776 ◽  
Author(s):  
M. Berardini ◽  
Jongseong Lee ◽  
Deborah Freedman ◽  
Jae Lee ◽  
T. J. Emge ◽  
...  
Keyword(s):  
Redox Stability

Electrochemical Performance Research of Mg Ion Doped LiMnPO4/C

2012 ◽  
Vol 554-556 ◽  
pp. 365-368
Author(s):  
Zeng Fu Wei ◽  
Wei Su ◽  
Shi Nian Liu
Keyword(s):  
Single Phase ◽  
Phenolic Resin ◽  
Reversible Capacity ◽  
Electrochemical Kinetics ◽  
Cation Substitution ◽  
Rate Performance ◽  
Ionic Radii ◽  
Similar Morphology ◽  
Performance Research ◽  
Mg Substitution

LiMn1-xMgxPO4/C(x=0, 0.01, 0.04, 0.05, 0.1) were synthesized by using wet-ballmilling and solid-state calcining with phenolic resin as the carbon source. All samples are single phase with a similar morphology, but the cation substitution results in a crystal lattice shrink because of the smaller ionic radii of Mg2+, the particles are small and homogeneous. CV, EIS and charge/discharge measurement shows that the Mg substitution leads to a significantly increased reversible capacity due to the enhanced electrochemical kinetics. LiMn0.96Mg0.04PO4/C calcined at 600°C has a discharge capacity of 144mAh/g at 0.05C. When charging-discharging by CC-CV-CC mode at high rates, LiMn0.96Mg0.04PO4/C composite exhibits a good cycle and rate performance.

Sign in / Sign up

Export Citation Format

Share Document