12/7/2019

共同利用共同研究公募中 1／6締め切り
http://www.cat.hokudai.ac.jp/r2_kyoten.html

In situ XAFS in Catalysis – merit,demerit and measurement.

Kiyotaka AsakuraInstitute for Catalysis,
Hokkaido University,
Sapporo, Japan

In situ(その場） and operando （反応中）

2in-operandoは誤用

https://youtu.be/ugzqLxiOlSM?t=11

反応が起こっているところの構造1

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3

なぜXAFS?
様々なオペランド手法

高い透過力があること
赤外、Raman,可視紫外
NMR,ESR（ただし本当のフロー
ガス共存下での測定が可能。は難しい）
濃度が低くても測定できる。

XPS（窓、差動排気）
TEM(窓、差動排気）反応物解析、TAP

アモルファスもOK
Ambient pressure XPS

Photon –in Photon Out

4
Operando XAFS

まさに反応中の構造を知ることができる。
過渡応答・振動反応なら、時間分解能が必要とされる。
QXAFS,DXAFS
定常条件なら、
Demerit
解析が複雑。
ガス漏れ、爆発など注意が必要。

2

12/7/20195
高時間分解能Step Scan XAFS

10min

Quick XAFS
ms－s
透過法、蛍光法、など様々な手法に対応、
DXAFS
マイクロs-s
透過法のみ、
サンプルの均一性を要求する

6
QEXAFSA technique that canmeasure one EXAFS
spectrum in a short time ( afew seconds in our system)by sampling signals fromionization chambers andmonochromator
continuously with scanningthe monochromator (on the
fly).

3

12/7/2019

7

Change during the reduction.
Slow
but highK. quality
and Fluorescence XAFS is applicatble.
1
K. Bando, Y. Koike, T. Kawai, G. Tateno, S.

XANEST. Oyama, Y. Inada, M. Nomura, K. Asakura, J. Phys. Chem.
C 2011, 115, 7466-7471 10.1021/jp11657z.

Every 1min

Every 1min

8
QXAFS Studies in SP8 (2004- )1.

K. Okumura, K. Yoshino, K. Kato and M. Niwa, Quick XAFS studies on the
Y-type zeolite supported au catalysts for CO-O-2 reaction. J Phys Chem B.
109,12380-12386(2005).

K. Okumura, T. Honma, S. Hirayama, T. Sanada and M. Niwa, Stepwise
Growth of Pd Clusters in USY Zeolite at Room Temperature Analyzed by
QXAFS. J.Phys.Chem.C. 112,16740-16747(2008).

K. Okumura, T. Honma, S. Hirayama, T. Sanada and M. Niwa, Stepwise Growth of Pd Clusters in
USY Zeolite at Room Temperature Analyzed by QXAFS. J.Phys.Chem.C. 112,1674016747(2008).

4

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9
DXAFS

A. Suzuki, Y. Inada, A.
Yamaguchi, T.
Chirara, M. Yuasa, M.
Nomura and Y.
Iwasawa, Time scaleand elementary stepsof CO induced
disintegration of
surface rhodium
clusters. Angewandte
Chemie Inter.Ed.
42,4795(2003).

QXAFSよりDXAFSがはやいです．

RITS

LiFePO4
electrode

1.M. Katayama, R. Miyahara, T.
Watanabe, H. Yamagishi, S. Yamashita,
T. Kizaki, Y. Sugawara and Y. Inada,
Development of dispersive XAFS system
for analysis of time-resolved spatial
distribution of electrode reaction.
J.Synchro.Rad. 22,1227-1232(2015).

Reversible Reaction Process of
Pt followed by DXAFS

Sum
mer
O
Chal
A(d empty state) R Pt-Pt =0.254 nm
leng
A.Suzuki, Y.Inada, M.Nomura, K.Asakura
B(Pt-Hbond
e inforation)
KEK
2

Hydrogenreaction on Pt
1.0
nanocluster

H

0.9

Ratio of species

t
0.8

A.Suzuki, to be published
0.7

Oxidation

1.0
0.8

0.4
0.2

0.2

B

0.0
2

4

11520

6

t/s

8

E/ eV
900 ms

0.0

10

11560

Energy / eV

11560

0.6

0.4

0

10

0.8

A

0.6

Reduction

1.0

0

2

11600

4

t/
s

11600
2010/8/25

6

8

10

8

5

12/7/2019

Pump Probe XAFS setup for Photocatalyst
Sample: 0.6 mM WO3 suspension
pump laser: 400 nm 270 mJ/cm2@945 Hz
X-ray pulse width: 100 ps(FWHM)

Honda-Fujishima effect
可視光応答型光触媒

2p→5d

J. Synchrotron Radiat. 2007, 14, 313.
J. Synchrotron Radiat. 2009, 16, 110.

Decay of X-ray absorption

R. Abe, et. al. J. Am. Chem.
Soc. 2008, 130, 7780-7781

Uemura, Y.; Uehara, H.; Niwa, Y.; Nozawa, S.; Sato, T.; Adachi, S.;
Ohtani, B.; Takakusagi, S.; Asakura, K. Chem. Lett. 2014, 43 977.

k = 0.5(1) ns -1

The excited state decayed in 10 ns.
→It was successfully fitted with a single exponential function.

6

12/7/2019

13

Assignment
White line
This is a dipole transition from 2p3/2 to 5d state.
Intensity is related to 5d empty state.
If 5d is occupied, white line decreases.
Low valence gives smaller white line

2nd derivatives

0.4

0.2

0.0

-0.2

t2g
-0.4

-0.6
10200

10210

10220

10230

10240

energy / eV

2nd derivative

Eg orbitals are occupied by excited electron

Photoexcited State of WO3 : LIII XANES
Uemura et al. Chem. Lett. 2014, 43, 977-979

W 5d0
eg
t2g

2p

t2g

eg

WO3
Oxygen 2p is excited to 5d eg ortbital not the bottom of d band7

12/7/2019

15

Conclusions from XANESIs it possible to excite the electron to eg?

Energy is necessary
W 5d>6.0 eV!!

eg

t2g

Excitation energy of laser

3 eV
O2p

WO3のDOSF. Wang, C. D. Valentin, G. Pacchioni,
J. Phys. Chem. C. 2012, 116, 8901

168

12/7/2019

SACLA : X-ray Free Electron Laser
SPring-8

Experiments at SACLA~30 fs~50 fsPhotoexcitation of WO3 : XFEL

SACLASample: 4 mM WO3 suspension
pump laser: 520 mJ/cm2@15 Hz
X-ray pulse width: 30 fs(FWHM)
Time resolution: 700 fs

Uemura, Y.; Kido, D.; Wakisaka, Y.; Uehara, H.; Ohba, T.; Niwa, Y.;
Nozawa, S.; Sato, T.; Ichiyanagi, K.; Fukaya, R.; Adachi, S.; Katayama,T.; Togashi, T.; Owada, S.; Ogawa, K.; Yabashi, M.; Hatada, K.;
Takakusa, S.; Yokoyama, Y.; Ohtani, B.; Asakura, K. Angew. Chem.Int.Ed
2016, 55, 1364.

Three distinct peaks were
found in the differential spectra.
peaks A ,B, C : decrease ofabsorption from eg orbitals ~200 pspeak B which was not found in
the previous experiments wasobserved.

9

12/7/2019

Changes of X-ray absorption at Peak A, B and C
Peak AThe same decay curve

k1 and k2 were
estimated as
0.007(1) ps-1
and 0.00056(5)ps-1, respectively

Peak B

Peak C

A*exp(-k1t) + B*exp(-k2t).

20First derivative and reference compound.

Photoabsorption is accompanied by theedge shift because of O2p to W 5delectron transfer occurs.

1012/7/2019

21

Comparison of derivative and difference spectra

derivative

Due to edge shift

Difference spectra

700 fsOccupation of d-state byphotoabsorption

Shift downward
and filled
W5+ is created during the photoabsorption
Due to edge shift

22

The change less than 200ps
t2g

eg
Based on the orthorhombic
stable at higher temperature

Based on Monoclinic
stable at room temperature
Ground state
Structure change occurs afterwards

Experimental

Calculation by Prof. Hatada
Structure transformation induces
more t2g and less eg

1112/7/2019

23

Scheme after the photoabsorption.
Orthorhombic like
local structure

In situ EXAFS
princilple put window away from furnace.

.

Window(Acrylic resin)
Water
Gas Water
Sample Gas
Thermocouple
X-ray
Io

I

Heater Gas
O-ring Water
Quartz Tube

High pressure cell
J.Phys.
Chem.93,4213(1989)
X-ray absorption,
Principles, applications,
techniques of EXAFS,SEXAFS, and XANES,New York, John Wiley &Sons, 1988.

Z.Phys.Chem.,144,105(1985).

Water

J.Synchro.Rad.8, 581(2001).

J.Chem.Phys. 70 (1979) 4849.

12

12/7/2019

Conversion reaction of methane to hydrocarbons.

25

MethaneAt 1000 K

In/SiO2 is a prominent catalyst for non-oxidative
coupling of CH4 [2].
1. Nishikawa, Y.; Ogihara, H.; Yamanaka, I., Liquid‐Metal Indium
Catalysis for Direct Dehydrogenative Conversion of Methane toHigher Hydrocarbons. ChemistrySelect 2017, 2 (16), 4572-4576.

26

XAFS measurement cell

1. XAFS cell was made-up ofquartz glass.
2. Resistance up to 1373 K evenin H2 or CH4 gas flow.

Front viewside view

Fabricated at Technical Division,
Institute of Catalysis,
Hokkaido University

13

12/7/2019

27
Activation process => Dynamic change occurs.
In catalysts are activated under the CH4 flow up to 1073 K

In foilIn foil

RT

RT

873 K

430K

430K

873K

873K

1073K

1073K

Conclusions
In-situ XAFS was used to identify
the structural changes of In/SiO2
during the activation process
At 300 K :In metallic particles

At 430 K :liquid In

Metamorphosis likeAt 873 K : In-X/SiO2
In-X might be the Indium carbide
At 1073 K :At 1173 K :In-X was disappearedand CO2 appeared in QMS
Fresh liquid In phase

Kashaboina, U.; Nishikawa, Y.; Wakisaka, Y.; Sirisit, N.; Nagamatsu, S.;
Bao, D.; Ariga-Miwa, H.; Takakusagi, S.; Inami, Y.; Kuriyama, F.; Dipu, A.
L.; Ogihara, H.; Iguchi, S.; Yamanaka, I.; Wada, T.; Asakura, K. Chem.
Lett. 2019, 48, 1145.

14

12/7/2019

29

Activated under different conditions.
10wt% In/SiO2 under CH4 , H2 and He flow activation
We increased the temperature with 10 K / min,from 300- 1173 K.
Temperature profile We found strong reduction of In Kedge jump in He flow activation.
 Reproduced 3 times.
 It indicates more In loss in He flow
than that of others.

Edge jump of In K-edge

Fourier Transforms of k3-weighted EXAFS
300 K

430 K

30

• Peak at 1.5 Å related tolighter element (O/C)
attached to In.
1173 KHe flow
873 K

1173 K

He > CH415

12/7/2019

31

Hypothesis
In/SiO2 during
the activation

473 K
melting873 K1173 K

+ “C”
CH4

H2

–‟O”
Reduction

–‟O”
In

SiO2

In-Ox

He
Formation,
Sublimationof In-Ox

Plausible pathway.. In2O3 is volatile at 1173 K(http://www.Americanelement.com)
Vapor pressure of In at 1173 K is 8 * 10-3 mbar.

High pressure cell under high pressure gas.

32

100 atm

Asakura, K.; Iwasawa, Y., Extended
X-ray Absorption Fine Structure
Studies on the Structure Change of
the Al2O3-attached [CoII]4 Catalyst
during a CO Oxidation Reaction.
J.Phys.Chem. 1989, 93, 4213-4218.

Cool down the windows sothat we can use Be windowor thick Plastic window

16

12/7/2019

Hydrodesulfurization(HDS) catalyst

Oyama, S. T.; Wang, X.; Lee, Y.-K.; Chun, W.J. J.Catal 2004, 221, 263.

It removes sulfur compounds from fossil fuel.

s

H2
+ H2S

s

Reactions are conducted under high pressure
condition in the presence of oil.

34
高温高圧に耐える窓材は？
Demands are “window materials must stand for highpressure and high temperature at the same time”.
Demands are “window materials must stand for high– Capillary cells
pressure and high temperature at the same time”.
• But curved window causes thickness effects
Capillarycells– Diamond,
Be andcauses
Al Flatwindows.
But curved window
thickness
effects
Diamond,
Be andAl Flatorwindows.
• Expensive(diamond)
toxic (Be)
toxic
(Be)
•Expensive
Diamond,(diamond)
Be and Alorarechemicallyand thermally not so
Diamond,stable. Be and Al are chemically and thermally not so stable.

Al window
N. Weiher et.al., J. Synchrotron Rad. 12(2005) 675.

J. D. Grunwaldt, et al.
Rev. Sci. Instrum. 76, (5),054104 (2005).

G. Sankar, and J. M. Thomas,
Topics.in Catal. 8, 1 (1999).

17

12/7/2019

Cubic BN 2番目に硬い物質

35cBN
Cubic BN is Second hardest material
Tensile strength = 1078.7 MPa

Sumiya, H.; Uesaka, N., High purity cBN
polycrystalline its high pressure synthesis andits fieature. New Diamond 1999, 15 (4), 14.

Diamond=2000 Mpa;Be=260 MPa
Previously cBN was made using binders and stregths was reduced.
Recently direct formation of cBN without binders by directly conversion at high pressure(7.7 GPa ) and high temperature(2400 K).
(Sumitomo Electro Engineering Co. Dr. Sumiya)

It is thermally stable upto 1273 K and chemically also stable.
600 μmの厚みで十分な透過性と30気圧の耐久性

A cell drawing .

Kawai, T.; Chun, W. J.; Asakura, K.; Koike, Y.; Nomura, M.; Bando, K. K.; Oyama, S. T.;
Sumiya, H. Review of Scientific Instruments 2008, 79, 014101.1.ｄ

36

Cartridge heaterC- BN

sampleVolt

Cross section
SUS315
3.5 kgFixed screw hole18

12/7/2019

37

XANES of Ni2P under reaction conditions.
Before reaction
1.5

10 h(a)

1.0

24 h

t

(b)
(c)

0.5

0.0
8300

8350
8400
8450
Energy /eV

8500

(k) oscillations of Ni K-edge
XANES for Ni2P on SiO2 before(a) and during the HDS
reaction 10 h and 24 h after
the introduction of oil (b) and(c), respectively. The Ni2P was
reduced at 723 K and cooled
to room temperature. The HDS
was carried out at 3 MPa and613 K.

30気圧613K モデル油中のXAFS
20 wt% tetralin, 77 wt% tetradecane, and 3 wt% DBT,
80cc /min H2

1.Kawai, T.; Chun, W. J.; Bando, K. K.; Oyama, S. T.; Sumiya,
H.; Asakura, K., A high-temperature and high -pressure liquidflow cell to measure operando XAFS spectra under thehydrodesulfurization reaction. Rev.Sci.Instrum 2005.
2.Kawai, T.; Bando, K. K.; Lee, Y. K.; Oyama, S. T.; Chun, W.
J.; Asakura, K., EXAFS measurements of a working catalyst in
the liquid phase: An in situ study of a Ni2P hydrodesulfurization
catalyst. J.Cat. 2006, 241, 20-24.
3.T.Kawai; S. Sato, K. K. B., W.-J.Chun, S.T.Oyama,Y.-K.Lee ;K.Asakura, Active Phase of Ni2P Observed by an Operando
XAFS. In TOCAT2006, Tokyo, 2006.

EXAFS of Ni2P under reaction conditions.

38

(k) oscillations of Ni K-edge EXAFS for Ni2P on SiO2 before (a)druing the HDS reaction 10 h after the introduction of oil (b).
0.2

Before reaction
a)

(k)

0.1

10 h

0.0

Ni2P structure のあらわ
な変化がない．
反応中安定である．

b)
-0.1

2

4

6
8-1
k / A

10

12

19

12/7/2019

39
High pressure liquid cell
window must be tolerable against high pressure and temperature.
Cubic BN is Second hardest material
Tensile strength = 1078.7 MPa
Diamond=2000 Mpa;Be=260 MPa

Before reaction

During reaction

XAFS of Ni2P in the presence of Oil
At 673 K; 3 MPa

Stable!!

Difference spectrum

40

チオフェン脱硫反応（1気圧）の脱硫反応
0.12

Simulated XAFS based on Ni-S bondNi – S (FEFF)
CN = 0.1, R = 0.227 nm,

0.10

HDS at 593 K

(k) /0.1

0.08
0.06

HDS at 553 K
0.04

HDS at 513 K

0.02
0.00
3

4

5

6

7

8

9

10

k / 10 nm-1

P

P

Ni

Ni

Ni
P

• CF results of Ni-S
R=0.227 nm； CN=0.1.
• Judging from the ratio of
surface Ni to the bulk ~0.5
S/Nisurf=0.2• Little reaction temperaturedependence

P

P

P
Ni

Ni

Ni
P

S

P

P

P

20

12/7/2019

41

But what is Ni-S for?
Ni-S is a spectator ?
Ni-S is a poison ?
Ni-S is included in an active site?

We carried out the simultaneous
measurements of in situ quick
XAFS,IR, and product analysis.

XAFS,IR,反応生成物分析同時測定
X-ray
Infrared
Thermocouple
HeaterSampleGas injection bulb

C4H4S + 2H2 → C4H8S
C4H8S + H2 → H2S + C4H8

42

Sample : Ni2P/MCM-41
35 mg, 15 mm Φ disk
45 deg tilted against Xray and
IR.
1.

2.

3.

4.

Bando, K. K.; Koike, Y.; Kawai, T.; Tateno, G.; Oyama, S.
T.; Inada, Y.; Nomura, M.; Asakura, K., Quick X-ray
absorption fine structure studies on the activation
process of Ni2P supported on K-USY. J. Phys. Chem. C
2011, 115 (15), 7466-.
Bando, K. K.; Wada, T.; Miyamoto, T.; Miyazaki, K.;
Takakusagi, S.; Koike, Y.; Inada, Y.; Nomura, M.;
Yamaguchi, A.; Gott, T.; Ted Oyama, S.; Asakura, K.,
Combined in situ QXAFS and FTIR analysis of a Ni
phosphide catalyst under hydrodesulfurization
conditions. J Catal 2012, 286 (0), 165-.
Wada, T.; Bando, K. K.; Miyamoto, T.; Takakusagi, S.;
Oyama, S. T.; Asakura, K., Operando QEXAFS studies ofNi2P during thiophene hydrodesulfurization: Direct
observation of Ni-S bond formation under reaction
conditions J.Synchrotro.Rad. 2012, 19 (2), 205-209.
Wada, T.; Bando, K. K.; Oyama, S. T.; Miyamoto, T.;
Takakusagi, S.; Asakura, K., Operando Observation of
Ni2P Structural Changes During Catalytic Reaction:
Effect of H2S Pretreatment. Chem. Lett. 2012, 41, 12381240.

21

12/7/2019

XANES, IR and MS changes during 513 K

43Bando, K. K.;et al J Catal 2012, 286 (0), 165.

XAFS
Ni-S

Infrared

HDSreaction starts

XANES, IR and MS changes during 513 K
Bando, K. K.;et al J Catal 2012, 286 (0), 165.

Ⅰ : Ni-S FORMATION

44

THT=Tetrahydrofuran
XAFS
Ni-S

Ⅱ : H2S & THT
production

Ⅲ : STEADYSTATEHDS reaction starts

2212/7/2019

Reaction mechanisms

45

Bando, K. K.;et al J Catal 2012, 286 (0), 165.

NiPS Formation processes

Ⅰ : Ni-S Formation

46

同時測定による反応機構提案
Bando, K. K.;et al J Catal 2012, 286 (0), 165.

THT

NiPS Formation processes

Hydorgenation processes

C-S bond cleavage

2H2

H2S

Ⅱ : REACTION
C-S bond cleavage

ICEAN20122012/Oct/24

23

12/7/2019

47
Simultaneously measurement of IR,XAFS and QMASSNiPS phaseis createdTetrahydrothiophene

NiPS structure is first formed and then reaction
starts with formation of THT as intermedite

電池駆動型マイクロガスセンサの開発

Suzuki, T.; Soma, S.; Nagase, T. In FujiElectric Review; Fuji
electric: 2012; Vol. 58, p 37.

●ガスの安全・安心に対する社会的要求高まる

開発中のガスセンサ概要⇒都市ガスの供給、ガス機器の両面での安全確保に加え、都市ガス警報器の普及が急務
SnO センサ層

検知ガス

2

でガスを検知●更なる普及推進のためにはガス警報器のコードレス化（電池駆動化）が必要
・停電時にも安全を確保可能
・台所ではＡＣ電源が確保しにくい・設置箇所に制約を受ける
・配線が美観を損ねる

高い信頼性を持ち、電池駆動できる超省電力型
ガスセンサの開発が必要：メタンガス
水素ガス

ダイアフラム径
500μm

図 薄膜ガスセンサチップ概略

PtﾄﾞｰﾌﾟSnO2触媒を採用することで特性が改善。

ＭＥＭＳ技術により、従来比1/2000以下の低消費電力を実現

P48

24

12/7/2019

In-situ XAFS実験

1) Murata, N.; Kobayashi, M.; Okada, Y.; Suzuki, T.; Nitani, H.; Niwa, Y.; Abe, H.; Wada, T.; Mukai, S.;
Uehara, H.; Ariga, H.; Takakusagi, S.; Asakura, K. Review of Scientific Instruments 2015, 86, 034102.
2) Murata, N.; Suzuki, T.; Kobayashi, M.; Togoh, F.; Asakura, K. Physical Chemistry Chemical Physics
2013, 15, 17938.

坂口伝熱製：1℃/1sec昇温・降温可能

X-ray hutch

Mass flow controller
Dry Air
DryAirベース
1%に調整

メタンガス
水素ガス

Cel
l

X-ray

In-situ cell

Temperature
controller

X ray
SSD detector

Gas conbustor Ventilation duct

Hollder
SampleWindow

P49

動径分布関数の比較☆CH4、H2ガス中のいずれもPt周囲とSn周囲の局所構造がSnO2の構造に酷似☆703 Kの水素ガス中において、Pt-Oの強度が減少

Pt-O
12

H2中
で減少

10

PtO2

8

Sn-O

703 K
Dry air中
CH4中
H2中

703 K

8

SnO2

6

6

Dry air中
CH4中
H2中

4

4
2

2
0

0

1

2

3

4

5

Pt 吸収端 EXAFS フーリエ変換

6

0
0

1

2

3

4

5

6

Sn 吸収端 EXAFS フーリエ変換

カーブフィッティング解析により、Pt-OとSn-Oの配位数、結合距離を明確し、構造について検証
P50

25

12/7/2019

Summary

1．Operando XAFS—High penetration ability.
２．High pressure Less than 100 bar and hightemperature less than 1200K are possible.
3. Future 時空間分析、高エネルギー分解、同時解析
で、触媒そのものが働いているときにそのまま測定。
https://youtu.be/ugzqLxiOlSM?t=11（https://www.youtube.com/watch?v=jIjxDWb3ADs）

52
Acknowledgement

Prof. Y.Iwasawa(ECU)
Prof. S.Ted Oyama(Univ.
Tokyo)
Dr. K.K.Bando(AIST)
Dr. T.Kawai
Dr. Y.Uemura(PSI)
Prof. S.Adachi(PF)Dr. M. Yabashi(SACLA)
Dr. T.Katayama(SACLA)
Dr. S.Nozawa(PF)Prof. M.Kimura(PF)Dr. H.Abe(PF)Dr. Y.Niwa(PF)Dr. H.Nitani(PF)Dr. Murata(Fuji)
Dr. Suzuki(Fuji)
Dr. U.Kashabonia(HU)
Prof. S.Iguchi(TIT)
Prof. I.Yamanaka(TIT)
Financial Support fromNEDO and JST

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