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1 Andreas Züttel, IfRES 27.01.2005
PROPERTIES OF BORANATES
ANDREAS ZÜTTEL
CONTENTS1) STABILITY2) KINETICS3) STRUCTURE OF LiBH44) MODEL5) FUTURE
EMPA Materials Sciences and TechnologyDept. Environment, Energy and MobilityAbt. Hydrogen & EnergyCH-8600 DübendorfSwitzerland
Solid State Physics of Energy Storage SystemsFaculty of SciencesDivision of Physics and AstronomyVRIJE UNIVERSITEIT AmsterdamThe Netherlands
Institute for Renewable Energy Switzerland (IfRES)Physics DepartmentUNIVERSITY of FRIBOURGSWITZERLAND
FuncHy 20061st Workshop of the Helmholtz InitiativeFunctional Materials formobile Hydrogen StorageGKSS Research Centre Geesthacht,September 20-22, 2006
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2 Andreas Züttel, IfRES 27.01.2005
HYDROGEN DENSITY
Ref: A. Züttel, “Materials for hydrogen storage”, materialstoday, Septemper (2003), pp. 18-27
HcovH±
H2
3
3 Andreas Züttel, IfRES 27.01.2005
COMPLEX HYDRIDES
( )0
00
S
HppTdecΔ
Δ==
+ -
Ref.: B. Bogdanovic et al., J. Alloys and Comp. 302 (2000), pp. 36-58
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4 Andreas Züttel, IfRES 27.01.2005
FIRST SYNTHESIS OF LiBH4H. I. SCHLESINGER, HERBERT C. BROWN, “Metallo Borohydrides. III. Lithium Borohydride”, J. of the Americ. Chemi. Society 62 (1940), pp. 3429-3435
SCHLESINGER H I; BROWN H C; ABRAHAM B; BOND A C; DAVIDSON N; FINHOLT A E; GILBREATH J R; HOEKSTRA H; HORVITZ L;HYDE E K; KATZ J J; KNIGHT J; LAD R A; MAYFIELD D L; RAPP L; RITTER D M; SCHWARTZ A M; SHEFT I; TUCK L D; WALKER A O, “New Developments in the Chemistry of Diborane and the Borohydrides: I. General Summary”, J. Am. Chem. Soc. (1953), 75, pp. 186-190
H. I. SCHLESINGER, HERBERT C. BROWN, JAMES R. GILBREATH AND J. J. KATZ, “Reaction of the Boron Halides with the Alkali Metal Hydrides and with Their Addition Compounds; A New Synthesis of Diborane”, J. Am. Chem. Soc. (1953), 75, pp. 195-199
H. I. SCHLESINGER, HERBERT C. BROWN, HENRY R. HOEKSTRA AND LOUIS R. RAPP, “Reactions of Diborane with Alkali Metal Hydrides and Their Addition Compounds. New Syntheses of Borohydrides. Sodium and Potassium Borohydrides”, J. Am. Chem. Soc. (1953), 75, 199-204
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5 Andreas Züttel, IfRES 27.01.2005
THERMAL DESORPTION OF H2 FROM OF LiBH4
Ref.: D. S. Stasinevich and G. A. Egorenko, Russian J. of Inorganic Chemistry 13(3) (1968), pp. 341-343
Polymorphic transformation
fusion
H2desorption
50% of H2desorption
1.5 mol H2LiH + B
I II III IV
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6 Andreas Züttel, IfRES 27.01.2005
STABILITY OF LiBH4
Ref.: D. S. Stasinevich and G. A. Egorenko, Russian J. of Inorganic Chemistry 13(3) (1968), pp. 341-343
LiBH4 LiH + B + 3/2H2ΔH = -68.9 kJ mol-1 H2ΔS = 99.9 J·K-1mol-1 H2
MeasurementΔH = -177.4 kJ mol-1 H2ΔS = 238.7 J·K-1mol-1 H2
LiBH4 Li + B + 2H2ΔH = -97.0 kJ mol-1 H2ΔS = 109.7 J·K-1mol-1 H2
IIIIIIIV
823 K753 K
703 K
Ref.: S.-I. Orimo, Tohoku Uni. Japan (2005)
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7 Andreas Züttel, IfRES 27.01.2005
THERMAL H2 DESORPTION FROM LiBH4
catalyzed
pure
into vacuum
Ref.: W. G. Brown, L. Kaplan, K. E. Wilzbach, J. Amer. Chem. Soc. 74 (1952), pp. 1343-1344
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8 Andreas Züttel, IfRES 27.01.2005
ACTIVATION ENERGY FOR LiBH4 LiH + B + 3/2 H2
catalyzed
pure
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9 Andreas Züttel, IfRES 27.01.2005
STRUCTURE OF LiBH4 AT 293K (20°C)
Orthorhombic symmetryspace group: Pnma (#62)a = 7.17858(4) Åb = 4.43686(2) Åc = 6.80321(4) ÅVol: 216.685 Å3, Z = 4
Atom x y zLi 0.1568 0.2500 0.1015 B 0.3040 0.25000 0.4305H1 0.900 0.25000 0.956 H2 0.404 0.25000 0.280 H3 0.172 0.054 0.428
Ref.: J-Ph. Soulié, G. Renaudin, R. Cerny, K. Yvon, J. Alloys and Comp. 346 (2002), pp. 200-205A. Züttel et al., Journal of Alloys and Compounds 356–357 (2003), pp. 515–520
SLS:GOZZO FabiaPATTERSON Bruce
Refinement:SHEPTYAKOV DenisFISCHER Peter
No single crystal exists!
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10 Andreas Züttel, IfRES 27.01.2005
PHASETRANSITIONS LiBH4
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11 Andreas Züttel, IfRES 27.01.2005Andreas Züttel, Switzerland, 10/5/20061
STRUCTURE OF LiBH4 AT 408K (135°C)
hexagonal symmetryspace group: P63mc (#186)a = 4.27631(5) Åc = 6.94844(8) ÅVol: 110.041 Å3, Z = 2
Atom x y zLi 0.3333 0.6666 0.0000 B 0.3333 0.6666 0.553 H1 0.3333 0.6666 0.370 H2 0.172 0.344 0.624
Ref.: J-Ph. Soulié, G. Renaudin, R. Cerny, K. Yvon, J. Alloys and Comp. 346 (2002), pp. 200-205
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12 Andreas Züttel, IfRES 27.01.2005
STABILITY OF LiBH4: DFT + PSEUDOPOTENTIAL
LiBH4 LiH + B + 3/2 H2Pnma phase
ΔH = 68.79 kJ·mol-1 H2Ref.: Terry Frankcombe, LIC / Theoretical Chemistry, University of Leiden, NL
ΔH = 68.90 kJ·mol-1 H2 @ 25°CRef.: Smith and Bass, J. Chem. Eng. Data 8 (1963), pp. 342
P63mc phase
ΔH = 54.08 kJ·mol-1 H2Ref.: Terry Frankcombe, LIC / Theoretical Chemistry, University of Leiden, NL
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13 Andreas Züttel, IfRES 27.01.2005Andreas Züttel, Switzerland, 10/5/20061
STRUCTURE PARAMETERS FOR LiBH4
Ref.: Zbigniew Lodziana and Tejs Vegge, "Structural stability of hydrides - LiBH4 revised", Physical Review Letters 93 (14): Art. No. 145501 (2004).
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14 Andreas Züttel, IfRES 27.01.2005
INTERMEDIATE PHASES
Ref: Nobuko Ohba, Kazutoshi Miwa, Masakazu Aoki, Tatsuo Noritake, Shin-ichi Towata, Yuko Nakamori, Shin-ichi Orimo, and Andreas Züttel, “First-principles study on the stability of intermediate compounds of LiBH4”, Phys. Rev. B 74, 075110 (2006)
LiBH4 → LiH + B + 3/2 H2
LiBH4
Li, B, 2H2
LiH, B, 3/2 H2
ΔH
LiBH4
LiBH4
Li, B, 2 H2
PnmaP63mc
liq.
ΔHf0 -194.2 kJ
ΔHStruc4.4 kJ
ΔHm7.1 kJ
ΔH90.7 kJ
ΔH49.1 kJ
Li2B12H12, 5/6 LiH, 13/12 H2ΔH
42.9 kJ
ΔHf0 -97.1 kJ
ΔHStruc2.2 kJ
ΔHm3.6 kJ
ΔH45.3 kJ
ΔH181.5 kJ
ΔHf0 -182.7 kJ
ΔH103.0 kJ
ΔH60.6 kJ
ΔH56 kJ
“LiBH2”
“LiBH3.6”
“LiBH3”
LiH
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15 Andreas Züttel, IfRES 27.01.2005
MECHANISM OF THE DECOMPOSITION (LiBH4)+
-+
-
+
-
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16 Andreas Züttel, IfRES 27.01.2005
STABILITY OF BHn AND BHn-
Ref.: Puru Jena , Virginia Commonwealth University, Richmond, VA (to be published).
Gradient Corrected Density Functional Theory
Energy gain in adding a H atomBHn-1 + H → BHn
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17 Andreas Züttel, IfRES 27.01.2005
STABILITY OF ABH4 AND AAlH4
0
0dec
SHT
Δ
Δ=
for p = p0
decomposition temperature
Ref.: Orimo S; Nakamori Y; Züttel A, “Material properties of MBH4 (M = Li, Na, and K)”, Materials Science and Engineering B108 (2004) , pp. 51–53
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18 Andreas Züttel, IfRES 27.01.2005
Ref.: Y. Nakamori, K. Miwa, A. Ninomiya, H. Li, N. Ohba, S.-I. Towata, A. Züttel, and Shin-ichi Orimo, Physical Review B 74,
045126 (2006)
Electronegativitiy of M for MBH4
*
M + nB + 2nH2 → M(BH4)n
STABILITY OF M(BH4)x
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19 Andreas Züttel, IfRES 27.01.2005
STABILITY OF BORANATES
Ref: Yuko Nakamori, Kazutoshi Miwa, Akihito Ninomiya, Haiwen Li, Nobuko Ohba, Shin-ichi Towata, Andreas Züttel, and Shin-ichi Orimo, “Correlation between thermodynamical stabilities of metal borohydrides and cation electronegativites: First-principles calculations and experiments”, Phys. Rev. B 74, 045126 (2006)
ΔH [kJ/mol BH4] = 248.7 χP – 390.8
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20 Andreas Züttel, IfRES 27.01.2005
STRUCTURE OF Mg[BH4]2Mg[BH4]2 exists in two crystalline modifications:
α-Mg(BH4)2 has a tetragonal lattice (a = 13.59, c = 16.51 Å), while
β-Mg(BH4)2 has a cubic face-centered lattice (a = 15.5 Å).
The temperature of the polymorphic transition is 186°. The density of the-modification is 0.989 g/cm3.Ref.: V. N. Konoplev and V. M. Bakulina, “Some properties of magnesium borohydride”, Russian Chemical Bulletin 20:1 (1971), pp. 136-138
Mg[BH4]2 Max Fichtner, FZKprivate communications J.-C. Zhao, GE Global Research (IEA talk, March 2006)
0 302520151052θ angle (°)
Patte
rn N
umbe
r
0
5
10
15
20
25
30
35
Mg(BH4)2
Crystalline MgH2
Mg
295°C
380°C
Amorphous MgH2
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21 Andreas Züttel, IfRES 27.01.2005
CHARGE DENSITY DISTRIBUTION
600
400
200
0
Inte
nsity
[Cou
nts]
6050403020102Θ [°]
30x103
20
10
0
Inte
nsity
[Cou
nts]
160140120100806040202Θ [°]
NEUTRON DIFFRACTION LiBD4
X-Ray DIFFRACTION LiBD4
Structure
Fullprof
Charge density maps
VASP, ElectrA
FT, MEM
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22 Andreas Züttel, IfRES 27.01.2005
CHARGE DENSITY IN LiBH4 AT 293K (20°C)
Orthorhombic symmetry
Ref.: F. Buchter, A. Züttel, Ph. Mauron, A. Borgshulte, S.I. Towata, S.I. Orimo, “Determination of the electronic charge density from synchrotron X-ray diffraction and neutron diffraction for light complex hydrides”, Phys. Rev. B (2006), to be submitted
0
0 0
0
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23 Andreas Züttel, IfRES 27.01.2005
REVERSIBILITY OF H2 SORPTION FROM LiBH4
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24 Andreas Züttel, IfRES 27.01.2005
REVERSIBILITY OF LiBH4
Ref. A. Züttel et al., to be published
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25 Andreas Züttel, IfRES 27.01.2005
SYNTHESIS OF LiBH4 FROM THE ELEMENTS
Li + B + 2H2 LiBH4p = 150 bar H2, T = 650°C
19581958