High Active Hydrogen Storage Alloy Mg2NiH4 and Mg2Ni Synthesized at Temperatures Lower than 733 K

2005 ◽  
Vol 488-489 ◽  
pp. 901-904 ◽  
Author(s):  
Xiao Feng Liu ◽  
Li Quan Li
Keyword(s):  
Low Temperature ◽  
Hydrogen Storage ◽  
Hydrogen Storage Alloy ◽  
Activation Process ◽  
Active Hydrogen ◽  
X Ray Diffraction ◽  
Hydrogen Storage Alloys ◽  
X Ray ◽  
Production Of Hydrogen ◽  
Temperature And Pressure

Hydrogen storage alloys Mg2Ni and Mg2NiH4 were synthesized at below 733 K by the process HCS. The product was examined by X-Ray diffraction and hydriding / dehydriding dynamics was tested. The result reveals that (1) High pure products of Mg2Ni and Mg2NiH4 can be obtained even at temperature 673 K and 0.1 MPa argon and 1.0 MPa hydrogen, respectively; (2) Both products are high active absorbing hydrogen > 3.2 mass % at 603 K without activation process. The result is very attractive due to the low temperature and pressure for the production of hydrogen storage alloys.

Phase Structure of (La,Mg,Nd)5Ni19 Hydrogen Storage Alloy

2013 ◽  
Vol 455 ◽  
pp. 66-70
Author(s):  
Qiang He ◽  
Yong Quan Guo ◽  
Zhen Zhen Zheng
Keyword(s):  
Hydrogen Storage ◽  
Structural Unit ◽  
Type Structure ◽  
Hydrogen Storage Alloy ◽  
X Ray Diffraction ◽  
Hydrogen Storage Alloys ◽  
Lattice Match ◽  
X Ray ◽  
Good Lattice ◽  
Three Phases

The crystal structure of (La,Mg,Nd)5Ni19alloy has been investigated using powder x-ray diffraction. A Rietveld refinement is used to determine the phase structures for tying to find out the correlations of lattices among the phases in this hydrogen storage alloy. The results show that the alloy consists of three phases, which correspond to (La,Mg)3Nd2Ni19with a Pr5Co19-type structure, La (Mg,Nd)Ni7phase with a Ce2Ni7-type structure and (La,Mg)3Nd2Ni19with a Ce5Co19-type structure. Mg and Nd substitute for La atom at the 4f position for Pr5Co19-type and Ce2Ni7-type structures and the 6c position for Ce5Co19-type structure, respectively. It induces a good lattice match along the a-axisand b-axis among the three phases. The three kinds of structures might form a rod-like shape structural unit by stacking along the c-axis. This phase constitution seems to be beneficial for the cyclic stability of the hydrogen storage alloys.

scholarly journals In situ X-ray Diffraction Investigation of Hydrogen Storage Alloys During Charge and Discharge

2016 ◽  
Vol 1 (4) ◽  
pp. 710-714
Author(s):  
Waldemir J. Paschoalino ◽  
Stephen J. Thompson ◽  
David Inwood ◽  
Claire Murray ◽  
Chiu C. Tang ◽  
...  
Keyword(s):  
Hydrogen Storage ◽  
X Ray Diffraction ◽  
Hydrogen Storage Alloys ◽  
X Ray

Microstructures and Electrochemical Properties of La0.7Ce0.3Ni3.7Co0.7-xAl0.2Mn0.4(Fe0.43B0.57)x (x = 0-0.4) Hydrogen Storage Alloys

2012 ◽  
Vol 608-609 ◽  
pp. 917-920
Author(s):  
Yu Zhou ◽  
Yan Ping Fan ◽  
Xian Yun Peng ◽  
Bao Zhong Liu
Keyword(s):  
Hydrogen Storage ◽  
Electrochemical Properties ◽  
Discharge Capacity ◽  
Secondary Phase ◽  
Cycling Stability ◽  
High Rate ◽  
X Ray Diffraction ◽  
Hydrogen Storage Alloys ◽  
X Ray ◽  
The Matrix

X-ray diffraction results indicate that pristine alloy has a single LaNi5 phase and the alloys containing Fe0.43B0.57 consist of the matrix LaNi5 phase and the La3Ni13B2 secondary phase. The abundance of La3Ni13B2 phase increases with increasing x value. Maximum discharge capacity of the alloy electrodes monotonically decreases from 336.1 mAh/g (x = 0) to 281.2 mAh/g (x = 0.4). High-rate dischargeability of the alloy electrodes first increases with increasing x from 0 to 0.20, and then decreases when x increases to 0.4. Cycling stability decreases with increasing x from 0 to 0.4.

Microstructure and Electrochemical Properties of La0.7Mg0.3(Ni1-xCox)3.5(x=0.0-0.2) Type Hydrogen Storage Alloy

2013 ◽  
Vol 365-366 ◽  
pp. 1198-1202
Author(s):  
Xiao Yun Zhao
Keyword(s):  
Hydrogen Storage ◽  
Electrochemical Properties ◽  
Discharge Capacity ◽  
Type Structure ◽  
Hydrogen Storage Alloy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electrochemical Discharge

La0.7Mg0.3(Ni1-xCox)3.5 (x=0.0-0.2) type hydrogen storage alloy was prepared. In order to optimizing the content of Co it was studied effects that Co replaced Ni on the structure and electrochemical properties of La0.7Mg0.3(Ni1-xCox)3.5(x=0.0-0.2) type hydrogen storage alloy X-ray diffraction (XRD) analyses showed that the alloys were composed of the LaNi5 phase with the CaCu5-type structure and the (La,Mg)2Ni7 phase with the Ce2Ni7-type structure. The maximum electrochemical discharge capacity increases with the increase of Co content. Moreover, the cycle stabilities of La0.7Mg0.3(Ni1-xCox)3.5 was improved remarkably by small quantity replacement Ni by Co, after 250 times, the discharge capacity was increased from 30% (x=0.0) to 65% (x=0.20).

Characteristics of AB3-Type Co-Free Hydrogen Storage Alloy in Low-Temperature Condition

2014 ◽  
Vol 974 ◽  
pp. 66-70
Author(s):  
Wei Li ◽  
Min Yu Zhang ◽  
Dao Bin Mu ◽  
Tao Yang ◽  
Feng Wu
Keyword(s):  
Low Temperature ◽  
Hydrogen Storage ◽  
Discharge Capacity ◽  
Hydrogen Storage Alloy ◽  
Hydrogen Storage Alloys ◽  
Electrochemical Tests ◽  
Temperature Heat ◽  
Metal Element ◽  
Free Hydrogen ◽  
Temperature Heat Treatment

In this paper, the characteristics of melted and annealed Co-free AB3-type hydrogen storage alloys in low-temperature condition were investigated by electrochemical tests. A series of Co-free AB3-type hydrogen storage alloys were synthesized with vacuum melting method, and be annealed by low-temperature heat treatment. The structures of alloys are simply discussed through SEM and XRD results. And discharge ability and cycle ability of alloys were tested. Experiment results indicate that characteristics of different AB3-type hydrogen storage alloys are affected by low-temperature obviously, and heated treatment could increase the discharge capacity of hydrogen storage alloy effectively, and improve the charge-discharge stability of alloy. Furthermore, non-metal element substituted alloy shows better Low-temperature applicability due to its weak crystallization. The discharge capacity of La0.7Mg0.3Ni2.9B0.05 alloy remains 91.2% after 30 cycles at 273K. And discharge capacity of heated La0.7Mg0.3Ni2.9(FeB)0.1 alloy could reach to 250mA·g-1.

Micro X-Ray Diffraction Study of Polycrystalline MgB 2 Wire and Evaluation of Carbon Doping Effect Via Low-Temperature Sintering

2019 ◽  
Author(s):  
Minoru Maeda ◽  
Dipak Patel, Dr. ◽  
Hiroaki Kumakura, Dr. ◽  
Gen Nishijima, Dr. ◽  
Akiyoshi Matsumoto, Dr. ◽  
...  
Keyword(s):  
Low Temperature ◽  
Diffraction Study ◽  
Carbon Doping ◽  
Doping Effect ◽  
Low Temperature Sintering ◽  
X Ray Diffraction ◽  
X Ray

The Application of X-Ray Diffraction at Elevated Temperatures to Study the Mechanism of Formation of Sodium Tripolyphosphate

1961 ◽  
Vol 5 ◽  
pp. 276-284
Author(s):  
E. L. Moore ◽  
J. S. Metcalf
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Amorphous Phase ◽  
Elevated Temperatures ◽  
Sodium Tripolyphosphate ◽  
X Ray Diffraction ◽  
Mechanism Of Formation ◽  
X Ray ◽  
Temperature Form ◽  
High Temperature Form

AbstractHigh-temperature X-ray diffraction techniques were employed to study the condensation reactions which occur when sodium orthophosphates are heated to 380°C. Crystalline Na4P2O7 and an amorphous phase were formed first from an equimolar mixture of Na2HPO4·NaH2PO4 and Na2HPO4 at temperatures above 150°C. Further heating resulted in the formation of Na5P3O10-I (high-temperature form) at the expense of the crystalline Na4P4O7 and amorphous phase. Crystalline Na5P3O10-II (low-temperature form) appears after Na5P3O10-I.Conditions which affect the yield of crystalline Na4P2O7 and amorphous phase as intermediates and their effect on the yield of Na5P3O10 are also presented.

scholarly journals X-ray diffraction analysis of kaolin M1 and M2 via the Williamson–Hall and Warren–Averbach methods

2021 ◽  
pp. 174751982098472
Author(s):  
Lalmi Khier ◽  
Lakel Abdelghani ◽  
Belahssen Okba ◽  
Djamel Maouche ◽  
Lakel Said
Keyword(s):  
Grain Size ◽  
High Temperature ◽  
Low Temperature ◽  
Diffraction Analysis ◽  
Mechanical Resistance ◽  
X Ray Diffraction ◽  
Integral Breadth ◽  
X Ray ◽  
Mullite Phase

Kaolin M1 and M2 studied by X-ray diffraction focus on the mullite phase, which is the main phase present in both products. The Williamson–Hall and Warren–Averbach methods for determining the crystallite size and microstrains of integral breadth β are calculated by the FullProf program. The integral breadth ( β) is a mixture resulting from the microstrains and size effect, so this should be taken into account during the calculation. The Williamson–Hall chart determines whether the sample is affected by grain size or microstrain. It appears very clearly that the principal phase of the various sintered kaolins, mullite, is free from internal microstrains. It is the case of the mixtures fritted at low temperature (1200 °C) during 1 h and also the case of the mixtures of the type chamotte cooks with 1350 °C during very long times (several weeks). This result is very significant as it gives an element of explanation to a very significant quality of mullite: its mechanical resistance during uses at high temperature remains.

Silicate-germanate K2Y[(Si3Ge)O10(OH)] with unusual complex corrugated layer and its correlation to ring silicate gerenite and chain silicate chkalovite

2020 ◽  
Vol 235 (4-5) ◽  
pp. 167-172
Author(s):  
Anastasiia P. Topnikova ◽  
Elena L. Belokoneva ◽  
Olga V. Dimitrova ◽  
Anatoly S. Volkov ◽  
Leokadiya V. Zorina
Keyword(s):  
Low Temperature ◽  
Cross Section ◽  
Complex Anion ◽  
Diffraction Experiment ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Chain Silicate ◽  
Novel Complex

AbstractA new silicate-germanate K2Y[(Si3Ge)O10(OH)] was synthesized hydrothermally in a system Y2O3:GeO2:SiO2 = 1:1:2 (T = 280 °C; P = 90–100 atm.); K2CO3 was added to the solution as a mineralizer. Single-crystal X-ray diffraction experiment was carried out at low temperature (150 K). The unit cell parameters are a = 10.4975(4), b = 6.9567(2), c = 15.4001(6) Å, β = 104.894(4)°; V = 1086.86(7) Å3; space group is P 21/c. A novel complex anion is presented by corrugated (Si,Ge) tetrahedral layers connected by couples of YO6 octahedra into the mixed microporous framework with the channels along b and a axes, the maximal size of cross-section is ~5.6 Å. This structure has similarity with the two minerals: ring silicate gerenite (Ca,Na)2(Y,REE)3Si6O18 · 2H2O and chain silicate chkalovite Na2BeSi2O6. Six-member rings with 1̅ symmetry as in gerenite are distinguished in the new layer. They are mutually perpendicular to each other and connected by additional tetrahedra. Straight crossing chains in chkalovite change to zigzag four-link chains in the new silicate-germanate layer.

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