conductivité ionique dans les verres - ustverre.fr
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Conductivité ionique dans les verresConductivité ionique dans les verres
A. Pradel, A. Piarristeguy, M. Ribes
Institut Charles Gerhardt Montpellier,
Équipe Chalcogénures et Verres,
CC1503, Université Montpellier 2,
Pl. E. Bataillon, F-34095 Montpellier cedex 5, France
Verres contenant des alcalins,
alcalino-terreux ou ions argent
Conduction Ioniqueélevée
Oxydes etChalcogénures
Dispositifs de stockage de l’énergie
Dispositifs de stockage de l’information
Batteries tout-solide
Mémoires ioniques
Spectroscopie d’impédance Complexe
Une succession de signaux de tension sinusoïdale U(ω) de fréquences
différentes est appliquée à l’échantillon
Intensité sinusoïdale I(ω) enregistrée
Impédance du matériau
Circuit modélisant le comportement électrique d’un verre
avec τ = RC (constante de temps)
e = épaisseur de l’échantillon,S = surface métallisée en contact avec l’électrode
Spectroscopie d’impédance Complexe
Diagramme de Nyquist
R= résistance
Conductivité
e = épaisseur de l’échantillon,S = surface métallisée en contact avec l’électrode
Ley de Arrhenius
Eσ : énergie d’activationσo: terme pré-exponentiel
)/exp(0 kTET σσσ −= 0ln
kTE)T.ln( σσ σ +−=
Dépendance avec la température : Loi d’Arrhenius
L’énergie d’activation est déterminée en calculant, par régression linéaire, la pente
de la droite ln(σΤ) = f(1/kT).
30 32 34 36 38 40-7
-6
-5
-4
-3
-2
-1
0
x = 10 x = 15 x = 20 x = 25
ln(σ
T) (S
cm
-1K
)
1 / kT (eV -1)
2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4
0.33
0.34
0.35
0.36
0.37
0.38
E σ (eV
)
ln(x) ( %at.)
0 4 8 12 16 20 24 280
5000
10000
15000
20000
σ 0 (S c
m-1K)
x (% at.)
Energie d’activation
Spectroscopie d’impédance Complexe : Système Agx(Ge0.25Se0.75)100-x
0 22000 44000 66000 88000 1100000
10000
20000
30000
40000
50000
60000
ω aumenta
x = 15
- Z´´
celd
a( ω
)
Z celda(ω )
294K 298K 303K 313K 323K 333K 343K 353K 363K
Terme pré-exponentiel
M. A. Ureña, A. A Piarristeguy. M. Fontana, B.Arcondo; SSI 176 (2005) 505.A. Piarristeguy, J. M. Conde Garrido, M. A. Ureña,M. Fontana, B. Arcondo; J. Non-Cryst.Sol. 353(2007) 3314.
Ion conducting glasses
(structure locale, 11B RMN, 31P RMN)System : 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]Mixed glass former effect: Oxide glasses
Mixed glass former effect: Chalcogenide glassesSystems : 0.3 Li2S 0.7[(1-x)SiS2 xGeS2], 0.5 Li2S 0.5[(1-x)SiS2 xGeS2] (structure locale, SAXS, Tg)
Ag-based glasses Systems : Agx(Ge0.25Se0.75)100-x, Ag2S-GeS2, Ag2S-GeS-GeS2, Ag2S-As2S3
(separation de phases, EFM, C-AFM)
System : 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]
Ion conducting glasses
Mixed glass former effect: Oxide glasses
Li2O
B2O3P2O5
2. Twin roller quenching
Extension of vitreous domain up to x=1
x=1
600 nm
x=0.64
x=0.64
600 nm
Thèse B. Raguenet
B. Raguenet, G. Tricot, G. Silly, M. Ribes and A. Pradel, Solid State Ionics, 208, 2012, 25-30
Activation energy Activation energy Conductivity Conductivity
Mixed glass former effect: Oxyde glassesSystem : 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]
System 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]: conductivity
B. Raguenet, G. Tricot, G. Silly, M. Ribes and A. Pradel, Solid State Ionics, 208, 2012, 25-30
Glass transition temperature Glass transition temperature
Mixed glass former effect: Oxyde glassesSystem : 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]
System 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]: Tg
B. Raguenet, G. Tricot, G. Silly, M. Ribes and A. Pradel, Solid State Ionics, 208, 2012, 25-30
System 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]: RMN
11B Chemical Shift / ppm-1001020
0.09
0.18
0.27
0.36
0.45
0.55
0.64
0.73
0.82
0.91
1.00
BO4#1
BO4#2
BO3
11B@18.8 T 31P@ 9.4 T
-60-40-2002031P Chemical Shift / ppm
0.09
0.18
0.27
0.36
0.45
0.55
0.64
0.73
0.82
0.91
0.00
Q3
Q2
Q1Q0
G. TricotTGIR Lille
ppm
-520 15 10 5 0 ppm
40
20
0
11B Chemical Shift / ppm
ppm
-520 15 10 5 0 ppm
40
20
0
11B Chemical Shift / ppm
x=0.36 x=0.64
BO3
BO4#1BO3
BO4#211B DQ-SQ @ 18.8 T
System 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]: RMN
B. Raguenet, G. Tricot, G. Silly, M. Ribes and A. Pradel, J. Mat. Chem. 21, 2011, 17693
0.0 0.2 0.4 0.6 0.8 1.0
0
10
20
30
40
50
60
B
O3 &
BO 4
x
BO3
BO4
BO4#1
BO4#2
System 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]: RMN
B. Raguenet, G. Tricot, G. Silly, M. Ribes and A. Pradel, J. Mat. Chem. 21, 2011, 17693
The coordination alone impacts theconductivity!Li+ acts as a charge compensator inthe presence of BO4 units. It is thenmore mobile than Li+ close to nonbridging oxygen
ü The Mixed Network Former Effect is directly related to the BO4units!
0.0 0.2 0.4 0.6 0.8 1.0-10
0
10
20
30
40
50
60
70
BO
4 & B
O3
x
BO3 BO4 log σ
-9.5
-9.0
-8.5
-8.0
-7.5
-7.0
-6.5
-6.0
-5.5
log
σ (S
/cm
)
The decrease in conductivity at highboron content occurs when the ratioBO3/BO4>1. BO3 units probably breakthe conduction paths.
The presence of phosphorous helpsessentially in favouring the existenceof BO4 against BO3
System 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]: RMN
B. Raguenet, G. Tricot, G. Silly, M. Ribes and A. Pradel, J. Mat. Chem. 21, 2011, 17693
System Li2S- [(1-x)SiS2-xGeS2]
Mixed glass former effect: Chalcogenide glasses
0.3 Li2S 0.7[(1-x)SiS2 xGeS2]
0.5 Li2S 0.5[(1-x)SiS2 xGeS2]
V.K. Deshpande, A. Pradel, M. Ribes, Mat. Research Bull., 23(3), 379 (1988)
ConductivityConductivity Activation energy Activation energy
0.0 0.2 0.4 0.6 0.8 1.00.30
0.35
0.40
0.45
0.50
0.5Li2S-0.5[(1-x)SiS2-xGeS2]
0.3Li2S-0.7[(1-x)SiS2-xGeS2]
E σ (e
V)
x
0.0 0.2 0.4 0.6 0.8 1.0
1E-6
1E-5
1E-4
1E-30.5Li2S-0.5[(1-x)SiS2-xGeS2]
x
σ (S
/cm
)
0.3Li2S-0.7[(1-x)SiS2-xGeS2]
System Li2S- [(1-x)SiS2-xGeS2]:: Conductivity and Eσ
Mixed glass former effect: Chalcogenide glasses
V.K. Deshpande, A. Pradel, M. Ribes, Mat. Research Bull., 23(3), 379 (1988)
0.0 0.2 0.4 0.6 0.8 1.0
175
200
225
250
275
300
325
350
375
x
T g ( o C
)
2 Tg and a minimum in ρ for ~50:50 ratio in former content
0.0 0.2 0.4 0.6 0.8 1.0
175
200
225
250
275
300
325
350
375T g (
o C)
x
0.3 Li2S 0.7[(1-x)SiS2 xGeS2] 0.5 Li2S 0.5[(1-x)SiS2 xGeS2]
Smooth change in Tg
0.0 0.2 0.4 0.6 0.8 1.01.9
2.0
2.1
2.2
2.3
2.4
2.5
x
ρ (g
/cm
3 )
System Li2S- [(1-x)SiS2-xGeS2]: Tg and density
Porod Law:aggregates or clusters of
50 Å in size
Debye-Bueche model:homogeneous glasses
System Li2S- [(1-x)SiS2-xGeS2]: SAXS
0.3 Li2S 0.7[(1-x)SiS2 xGeS2]
A. Pradel, Ch. Rau, D. Bittencourt, P. Armand, E. Philippot, M. RibesChemistry of Materials, 10 (8), 2162-2166 (1998).
amorphous
GeS2
amorphous
SiS2
Addition of Li2S
Preferential destruction of edge sharing tetrahedra(29Si NMR investigation)
Different medium range order
No possible mixing of the two formers
Complete phase Separation
(Tenhover 1983)
xLi2S- (1-x)SiS2
x=0.3 different MRO phase separation
x=0.5 similar MROComplete solid solution
System Li2S- [(1-x)SiS2-xGeS2]: Structure
A. Pradel, Ch. Rau, D. Bittencourt, P. Armand, E. Philippot, M. RibesChemistry of Materials, 10 (8), 2162-2166 (1998).
with 0 < x < 30 % at.
Samples
Agx(Ge0.25Se0.75)100-x
0 5 10 15 20 25-13
-12
-8
-7
-6
-5
-4
log
σ (Ω
−1 c
m-1)
% at. Ag
-13
ConductivityConductivity
7-8 orders of magnitude
A sudden break in the
« conductivity vs Ag content »
curve for 8-10% in Ag
Structure / Electrical properties: Ag-Ge-Se(S) systems
M. A. Ureña, A. A Piarristeguy. M. Fontana, B. Arcondo; SSI 176 (2005) 505.A. Piarristeguy, J. M. Conde Garrido, M. A. Ureña, M. Fontana, B. Arcondo;J. Non-Cryst.Sol. 353 (2007) 3314.
EFM V = - 5V
Clear-areas (Ag-poor phase)
FE-SEM
Ag5
Ag15
3μm
3μm Dark-areas (Ag-rich phase)
1.0µm
1.0µm
Ag5
Ag15
Ag5
Dark-areas (Ag-poor phase)
Clear-areas (Ag-rich phase)
Microstructural study : Agx(Ge0.25Se0.75)100-x glasses
UEFMD
dsample
cantilever
A.A. Piarristeguy, M. Ramonda, M.A. Ureña, A. Pradel, M. Ribes, J. Non-Cryst. Solids 353 (2007) 1261-1263.
Ag-rich phaseembedded in Ag-poor phase
Ag-rich phaseis the connecting
phase
Percolation threshold
350nm
Ag1
1.0µm
Ag5
1.0µm
Ag25
1.0µm
Ag20
1.0µm
Ag15
0 5 10 15 20 25-14
-12
-10
-8
-6
-4
-2
log
σ (S
cm
-1 )
at. % Ag
Kawasaki et al. Ureña et al.
& Piarristeguy et al.
Microstructural study: FE-SEM and EFMMicrostructural study : Agx(Ge0.25Se0.75)100-x glasses
V. Balan, A.A. Piarristeguy, M. Ramonda, A. Pradel, M. Ribes, J. Optoelect. and Adv. Material Vol.8 ISS.6 (2006) 2112-2116.
Ag2S-GeS2 (15%Ag)
FE-SEM EFM -3V
Ag2S-GeS-GeS2 (16,7%Ag)
0,01 0,1 1 10 100-16
-14
-12
-10
-8
-6
-4
-2
log
σ (S
/cm
)
%Ag
Ag2S-GeS-GeS2
Ag2S-GeS2
1.0µm
1.0μm
E. Bychkov, V. Tsegelnik, Yu. Vlasov, A. Pradel, M. Ribes, J. Non-Cryst.Solids 208, 1 (1996).A. Pradel, N. Kuwata, M. Ribes, J. Phys.: Condens. Matter 15, 1561(2003).
Microstructural study : Ag-Ge-S glasses
V. Balan, A.A. Piarristeguy, M. Ramonda, A. Pradel, M. Ribes, J. Optoelect. and Adv. Material Vol.8 ISS.6 (2006) 2112-2116.
ü The current through the Ag-rich phase increases when the
applied dc bias increases.
ü Practically any current flows through the Ag-poor phase.
400nm- 0,60 V- 0,80 V
- 0,45 V- 0,90 V- 1,25 V- 0,95 V- 1,15 V
- 0,65 V- 0,85 V- 0,55 V- 0,75 V- 0,45 V- 0,70 V- 0,50 V 400nm- 0,60 V- 0,80 V
- 0,45 V- 0,90 V- 1,25 V- 0,95 V- 1,15 V
- 0,65 V- 0,85 V- 0,55 V- 0,75 V- 0,45 V- 0,70 V- 0,50 V
µm
I (p
A)
I1
I2
V=V1
Ag20(Ge0.25Se0.75)808,17pA
-31,37pA
IA
VDC
Conductivity of each phase: Conductive Atomic Force Microscopy
ü C-AFM
A.A. Piarristeguy, M. Ramonda, N. Frolet, M. Ribes, A. Pradel, Solid State Ionics 181 (2010) 1205-1208.
-4.5 -4.0 -3.5 -3.0 -2.5 -2.0 -1.5 -1.0 -0.5-12
-11
-10
-9
-8
-7
-6
Voltage (V)
Cur
rent
(pA
)
Ag10 Ag15 Ag20
Qualitative evaluation of conductivity
If the contact is assumedto be circular and Ohmic in nature
then the relation between the resistance R and the resistivity ρ is
given by the basic spreadingresistance formula R ~ ρ/4r where r is
the radius of the contact
For the tip radius: : r∼ 10 nm
σ ∼ 0,3 x 10-6 Ω-1cm-1
to 3 x 10-6 Ω-1cm-1
with increasing of the silver content in the samples.
For the tip radius: : r∼ 10 nm
σ ∼ 0,3 x 10-6 Ω-1cm-1
to 3 x 10-6 Ω-1cm-1
with increasing of the silver content in the samples.
Conductivity of each phase: Conductive Atomic Force Microscopy
ü C-AFM
A.A. Piarristeguy, M. Ramonda, N. Frolet, M. Ribes, A. Pradel, Solid State Ionics 181 (2010) 1205-1208.
Conclusion
System : 45 Li2O – 55 [x B2O3 – (1-x) P2O5)]
System : 30 Li2S – 70 [x SiS2 – (1-x) GeS2)]
System : Agx(Ge0.25Se0.75)100-x
Evolution non linéaire de la conductivité liée à la stabilisation des BIV
en présence d’entités phosphate
Augmentation de la conductivité quand Ge/Si ~ 1 due à une séparation de phase
Saut de conductivité de 8 ordres de grandeur due à la percolation d’une phase riche en argent
Rôle important de la structure sur la mobilité des ions dans les verres
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