In s

itu

stud

ies

of h

ydro

gen

deso

rpti

onfr

om m

etal

lic h

ydri

des

by n

eutr

on d

iffr

acti

on

M. L

atro

che,

V. P

aul-B

onco

ur, F

. Cue

vas

Inst

itut

de C

him

ieet

des

Mat

éria

uxde

Par

is E

stIC

MPE

-U

MR

7182

-CN

RSTh

iais

, Fra

nce

Shor

t in

trod

ucti

on t

o m

etal

lic h

ydri

des

(MH

)

Neu

tron

dif

frac

tion

for

MH

inve

stig

atio

n

oSt

eady

sta

te s

truc

tura

l ana

lysi

s

oO

ut o

f eq

uilib

rium

stu

dy b

y co

uple

d TD

S/N

D

The

pecu

liar

case

s of

TiN

iHx

and

YFe 2

Hx

Conc

lusi

ons

Out

line

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Solid

gas

rou

te (

P eq

, C(x

) , T

)

M +

x /2

H2

MH

x

Shor

t intr

oduc

tion

to

met

allic

hyd

ride

sM

etal

lic h

ydri

de f

or s

olid

gas

sto

rage

ln(P

H2)

ln(P

H2)

T 4 T c T 3

T 2 T 1

+

x(H

/M)

min

max

P eq3

P eq1

P eq2

ln(P

H2) =

H

/RT

- S/

R

1/T

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

300

250

200

150

100

50

0,30

0,25

0,20

0,15

0,10

0,05

0,00

-0,0

5

E (V) vs Cd/Cd(OH)2

Q(m

Ah.g

-1)

Non

aqu

eous

ele

ctro

chem

ical

rou

te

MH

x+

x Li

++

x e-

M +

x L

iH

0

1000

2000

3000

4000

050

010

0015

0020

00

Ah/L

Ah/K

g

grap

hite

AB5H

5

MgH

2

TiH

2

TiFe

H2

ZrV

2H4.

9

Mg 2

NiH

4

040

00

Li

Y. O

umellal,

W. Za

ïdi,

J-P

Bonn

et,F

. Cu

evas

, M

. La

troc

he, J.

Zha

ng,

J-L

Bobe

t, A

. Ro

ugier

and

L. A

ymar

d. I

JHE,

37

(201

2) 7

831-

7835

Hg/

HgO

v

sV

in

92

6.0

ln2

PE

Heq M

HnFRT

x

Elec

troc

hem

ical

rou

te (

E eq,Q

(x),

T)

M +

xH

2O +

x e

-M

Hx

+ xO

H-

Shor

t intr

oduc

tion

to

met

allic

hyd

ride

sM

etal

lic h

ydri

de f

or e

lect

roch

emic

al s

tora

ge

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

NiM

H t

ract

ion

batt

erie

s fo

r N

ice

tram

s

Some

succ

essf

ul a

pplic

ations

of

hydr

ides

…

HEV

Toy

ota

Priu

s

Oth

er a

pplic

atio

ns-

emer

genc

y lig

ht u

nits

, tel

ecom

mun

icat

ions

, cor

dles

s va

cuum

...

MgH

2

Mg

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Crys

tal s

truc

ture

det

erm

inat

ion

-Q

uant

ific

atio

n an

d lo

cati

on o

f H

(D) c

onte

nt

-Evi

denc

e of

pha

se t

rans

itio

ns a

s a

func

tion

of

H(D

) con

tent

Prac

tica

l adv

anta

ges

of u

sing

ND

as

diff

ract

ion

tool

:

-Bu

lk a

naly

sis

(hig

h pe

netr

atio

n de

pth

of n

eutr

ons)

-A

dapt

able

sam

ple

envi

ronm

ent

(fur

nace

, cry

osta

t, e

lect

roch

emic

al c

ell…

)

-A

dapt

ed t

ime

reso

luti

on f

or t

herm

al d

esor

ptio

n

Inne

r N

i cou

nter

-ele

ctro

deIn

ner

Ni c

ount

er-e

lect

rode

Hyd

ride

ele

ctro

deH

ydri

de e

lect

rode

oute

r N

i cou

nter

-ele

ctro

deou

ter

Ni c

ount

er-e

lect

rode

Silic

a c

ell

Silic

a c

ell

time

2La

troc

he e

t al. JA

LCOM

293

-295

(19

99) 67

3

Exam

ple:

In-

situ

ND

of

LaN

i 5-ty

pe e

lect

rode

s

Neu

tron

diffr

action

for

MH inv

estiga

tion

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Gas

rele

ase

mea

sure

men

t (H

2) w

hile

hea

ting

in a

low

pres

sure

atm

osph

ere

Pote

ntia

l ene

rgy

diag

ram

s

T (K)

t (s

)

b (K

/s)

Hea

ting

ram

p

T

Ther

mal d

esor

ption

spec

tros

copy

(TD

S)

TDS

Spec

trum

dn/dt(P)

T (K

)

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Var

iatio

n of

P in

th

e ch

ambe

rR

emov

al o

f gas

by

pum

pingP

KTS

dtdPK

TVdtdn

TDS:

Exp

erim

enta

l met

hod

P

Pum

p

SV,

T

dn/d

t

(QM

S)

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Ther

mal d

esor

ption

spec

tros

copy

(TD

S)

Var

iatio

n of

P in

th

e ch

ambe

rR

emov

al o

f gas

by

pum

pingP

KTS

dtdPK

TVdtdn

TDS:

Exp

erim

enta

l met

hod

P

Pum

p

SV,

T

dn/d

t

(QM

S)

Smal

l vol

ume

(V)

Hig

h pu

mpi

ng r

ate

(S)

Pdtdn

TDS

Spec

trum

dn/dtP

T (K

)

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Ther

mal d

esor

ption

spec

tros

copy

(TD

S)

Tem

pera

ture

ass

essm

ent

of d

iscr

ete

deso

rpti

on “s

tate

s”(T

DS

peak

s)

Popu

lati

ons

(inte

grat

ed a

reas

) and

rel

ated

act

ivat

ion

ener

gies

(Kis

sing

er p

lots

)

Det

erm

inat

ion

of r

ate

limit

ing

step

s (s

urfa

ce, t

rapp

ing,

dif

fusi

on, p

hase

tr

ansf

orm

atio

n) w

ith

a va

lid k

inet

ic m

odel

: fu

ll sp

ectr

a de

scri

ptio

n.

c) H/M

Mea

sure

dSi

mul

ated

PCT

isot

herm

s fo

r si

mul

atio

n

Ster

n et

al.

J. P

hys.

F:

Met

. Ph

ys. 14

(198

4)16

25Ex

ampl

e: T

DS

from

PdH

x

+

+

TDS:

wha

t info

rmat

ion

can

be o

btaine

d ?

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

TDS

vs.

ND

TDS

ND

Am

ount

of

deso

rbed

H2

Am

ount

and

loca

tion

of

H in

bul

k

Des

orpt

ion

mec

hani

sm

Surf

ace

reco

mbi

nati

on

H –

Dif

fusi

on

Phas

e tr

ansf

orm

atio

n

Crys

tal s

truc

ture

Phas

e tr

ansf

orm

atio

n vs

H-c

onte

nt

Ord

er-d

isor

der

tran

siti

ons

Am

orph

isat

ion

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Combi

ned

mea

sure

men

ts T

DS

–ND

Silic

a co

ntai

ner

Vacu

um a

nd T

con

nect

ions

Neu

tron

bea

m li

ne I

LL –

D1B

MH

sam

ple

Neu

tron

bea

mFu

rnac

e

4OO

Det

ecto

rs

Ther

moc

oupl

e Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

The

case

of

TiNi-

H2

Sorp

tion

pro

pert

ies

of t

he T

iNi-

H2sy

stem

Burc

h an

d M

ason

, J.

Che

m. So

c. F

arad

ay T

rans

. I

75 (19

79) 56

1

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

0.1110

Tem

pera

ture

(°C

)

5277

102

127

152

y(

)

PH2 (bar)

H /

TiN

i-pha

se

-pha

se

PCT

Ti Ni

Abs

orpt

ion

by s

olid

gas

rea

ctio

n: T

= 1

50°C

, PD

2=

4 M

Pa, t

= 2

wee

ks

Mea

sure

d co

ncen

trat

ion:

TiN

iD1.3

5

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Pm

mVo

l/Ti

Ni=

27

Å3

Pm

mD

/TiN

i= 0

.29

Vol/

TiN

i= 2

8.7

Å3

3.05

7 Å

3.057 Å

Stru

ctur

al p

rope

rties

of t

he

phas

e

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Ti Ni

H(D

)

I4/m

mm

D/T

iNi=

1.14

3.12

2 Å

3.093 Å

Ti Ni

H(D

)

Stru

ctur

al p

rope

rties

of t

he

phas

e

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Soub

eyro

uxet

al.,

JAL

COM

196

(19

93) 12

7

TDS

One

–ste

p de

sorp

tion

010

020

030

040

050

0-0

.3

-0.2

-0.10.0

Heat flow (W/g)

T(°C

)

Exo

DSC

Thre

e–st

ep d

esor

ptio

n

tran

sfor

mat

ion

?Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Hyd

roge

n de

sorp

tion

fro

m T

iNiH

1.4

300

400

500

600

700

0123456789

P (bar)T(

K)

300

400

500

600

700

0123456789

P (bar)

T(K

)

Coup

led

TDS-

ND e

xper

imen

t

TDS T

(K)

ND

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

-TiN

iH1.4

-TiN

i

Am

orph

isat

ion

Inte

rmed

iate

phas

e (

)

Crys

talli

zati

on

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Resu

lts

of R

ietv

eld

refine

men

t

300

350

400

450

500

550

020406080100

Phase content (wt% )

T (K

)

pha

se p

hase

pha

se

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

P4/m

mm

D/T

iNi=

0.7

Vol/

TiN

i= 2

9.4

Å3

Pmm

D/T

iNi=

0.2

9Vo

l/Ti

Ni=

28.

7 Å

3

I4/m

mm

D/T

iNi=

1.14

Vol/

TiN

i= 3

0.1

Å3

3.12

2 Å

3.093 Å

3.12

9 Å

3.001 Å

3.05

7 Å

3.057 ÅTi Ni

H(D

)

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

300

400

500

600

700

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

TD

S (s

pect

rum

inte

grat

ion)

ND

(D

-occ

upan

cies

)Deuterium content (D/TiNi)

T(K

)

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Compa

riso

n of

ND a

nd T

DS

H-c

onte

nts

100

200

300

400

500

-0.6

-0.4

-0.20.0

0.2

Heat Flow (W/g)

T(°C

)

Exo

Des

orpt

ion

H2

300

400

500

600

700

0123456789

P (bar)

T(K

)

TDS

Crys

talli

sati

on

ND

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Compa

riso

n of

ND,

TDS

and

DSC

DSC

The

case

of

YFe 2

-H2

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Mul

ti-p

eak

TDS

spec

tra

of L

aves

C15

hydr

ides

att

ribu

ted

to

H-d

esor

ptio

n fr

om e

nerg

etic

ally

dif

fere

nt in

ters

titi

al s

ites

Mot

ivat

ion

Ster

n et

al.

JALC

OM

88

(198

2) 4

31Pa

rk e

t al.

Scr.

Met

all.

23 (19

89) 15

25

HfV

2Er

Fe2

AB 2

Dx

A2B

2x

3

AB 3

x >

3

A B

ND

: Onl

y 2

type

s of

sit

e oc

cupi

ed !

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

300

350

400

450

500

550

600

650

0.0

5.0x

10-5

1.0x

10-4

1.5x

10-4

2.0x

10-4

2.5x

10-4

3.0x

10-4

3.5x

10-4

4.0x

10-4

-dx/dt (H u.f.-1

s-1

)

T(K

)

Coup

led

TDS-

ND e

xper

imen

t fo

r YF

e 2D

4.2

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

380K

Ord

er-d

isor

der

tran

siti

ons

Phas

e tr

ansf

orm

atio

ns

mon

oclin

ic

C15

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Coup

led

TDS-

ND e

xper

imen

t fo

r YF

e 2D

4.2

01

23

4

10-3

10-2

10-1

100

101

' 3 /

' 4

' 2 /

' 3

' 1 /

' 2

/ ' 1

408

K37

3 K

473

K

P (bar)

x (D

/YFe

2)

01

23

45

400

450

500

550

600

CubicC15

Tetragonal

cubic2a Tetragonal

CubicC15

triclinic

monoclinic

Orthorhombic

T=30

0 K

V (Å3)

x (D

/f.u.

)0

12

34

5

400

450

500

550

600

CubicC15

Tetragonal

cubic2a Tetragonal

CubicC15

triclinic

monoclinic

Orthorhombic

T=30

0 K

V (Å3)

x (D

/f.u.

)0

12

34

5

400

450

500

550

600

CubicC15

Tetragonal

cubic2a Tetragonal

CubicC15

triclinic

monoclinic

Orthorhombic

T=30

0 K

V (Å3)

x (D

/f.u.

)

-M

ulti

-pla

teau

isot

herm

s

Ther

mod

ynam

ic &

cry

stal s

truc

ture

for

YFe

2–D

2

V. P

aul-

Bonc

our,

JSS

C 14

2 (1

999)

120

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Succ

essi

ve p

hase

tra

nsfo

rmat

ion:

Joh

nson

-Meh

l-Avr

ami(

JMA

) equ

atio

n

i

ii

iE

RTk

F)

(ex

p1

2

ii

ii

ii

iF

Fk

dtdF/)1

( )1

ln(

)1(

dtdFx

dtdxi

i

n i1

it

kF

ii

)(

exp

1RTE

kk

io

iex

p,

, K o

~ hT

/K ~

10-1

3s-

1

J. F

arja

s, P

. Ro

ura,

"M

odificat

ion

of t

he

Kolm

ogor

ov-J

ohns

on-M

ehl-

Avra

mir

ate

equa

tion

for

no

n-isot

herm

al e

xper

imen

ts a

nd it

s an

alyt

ical

solution

", A

cta

Mat

er.,

54

(200

6) 5

573-

5579

Fit

of T

DS

spec

trum

to

i-pha

se t

rans

form

atio

ns

Simulat

ion

of t

he T

DS

spec

trum

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Peak

Ea

(kJ/

mol

)n

x (D

/f.u

.)1

123.

41.5

0.34

212

7.5

1.10.

73

313

3.5

1.10.

78

413

9.8

0.7

0.40

514

8.1

0.7

0.35

615

8.9

0.7

0.37

717

1.40.

71.2

2

300

350

400

450

500

550

600

650

0.0

1.0x

10-4

2.0x

10-4

3.0x

10-4

4.0x

10-4

TP i

Fit

TPi

Dat

a

1

-dx/dt (H f.u-1

s-1

)

T (K

)

32

45

6

7

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Fit

of t

he T

DS

spec

trum

01

23

45

400

450

500

550

600

CubicC15

Tetragonal

cubic2a Tetragonal

CubicC15

triclinic

monoclinic

Orthorhombic

T=30

0 K

V (Å3)

x (D

/f.u.

)0

12

34

5

400

450

500

550

600

CubicC15

Tetragonal

cubic2a Tetragonal

CubicC15

triclinic

monoclinic

Orthorhombic

T=30

0 K

V (Å3)

x (D

/f.u.

)0

12

34

5

400

450

500

550

600

CubicC15

Tetragonal

cubic2a Tetragonal

CubicC15

triclinic

monoclinic

Orthorhombic

T=30

0 K

V (Å3)

x (D

/f.u.

)

0

1.2

1.751.95

3.3

2.5

Peak

x (D

/f.u

.)A

ssig

ned

Phas

e Tr

ansf

orm

atio

n1

0.34

YFe 2

D4.

2YF

e 2D

3.85

20.

73YF

e 2D

3.85

YFe 2

D3.

15

30.

78YF

e 2D

3.15

YFe 2

D2.

35

40.

40YF

e 2D

2.35

YFe 2

D1.9

5

50.

35YF

e 2D

1.95

YFe 2

D1.6

0

60.

37YF

e 2D

1.60

YFe 2

D1.2

0

71.2

2YF

e 2D

1.20

YFe 2

3.5

4.2

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

350

400

450

500

550

600

650

400

420

440

460

480

500

01234

C15

-Vol

ume

V (Å3)

T (K

)

Deuterium content (D/f.u.)

Supe

rstru

ctur

e xPD

(D

-occ

upan

cies

) x

TDS (s

pect

rum

inte

grat

ion)

T. L

eblond

et a

l., I

JHE,

34(

2009

) 22

78

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Compa

riso

n of

ND a

nd T

DS

H-c

onte

nts

Conc

lusion

s (I

)

Ther

mal

des

orpt

ion

from

TiN

iD1.4

hydr

ide

occu

rs t

hrou

gh a

n

inte

rmed

iate

d hy

drid

e ph

ase

of m

ediu

m H

-con

tent

: -T

iNiD

0.7.

phas

e tr

ansf

orm

atio

n ge

nera

tes

com

poun

d am

orph

isat

ion.

DSC

mea

sure

men

ts a

re e

xpla

ined

by

the

com

bine

d ef

fect

s of

endo

ther

mic

hyd

roge

n de

sorp

tion

and

exo

ther

mic

allo

y

crys

talli

zati

on. Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Mul

ti-p

eak

TDS

spec

trum

for

YFe

2hy

drid

e is

wel

l-des

crib

ed b

y

cons

ecut

ive

phas

e tr

ansf

orm

atio

ns.

Mul

tipl

e C1

5 La

ves

phas

es h

ave

been

evi

denc

ed b

y N

D a

nd X

RD

diff

ract

ion

mea

sure

men

ts .

Sam

e de

scri

ptio

n m

ay a

ccou

nt f

or m

ulti

-pea

k TD

S sp

ectr

a

obse

rved

for

man

y C1

5 La

ves

phas

es.

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Conc

lusion

s (I

I)

TDS

set-

up c

an b

e ea

sily

impl

emen

ted

in N

D b

eam

-line

Coup

ling

of T

DS

-N

D t

echn

ique

s is

a v

ery

powe

rful

tool

to

char

acte

rize

hyd

roge

n de

sorp

tion

fro

m s

olid

s,

part

icul

arly

whe

n ph

ase

tran

sfor

mat

ions

tak

e pl

ace

Neu

tron

s fo

r M

HIn

trod

uction

Case

of

TiNiH

xCa

se o

f YF

e 2H

xCo

nclusion

s

Conc

lusion

s (I

II)

Ack

nowl

edgm

ents

F. C

ueva

s

V. P

aul-

Bonc

our

T.

Lebl

ond