The sensitivity and resolution development of X-ray spectroscopy –smaller, faster, thinner and sparser samples

Institute for CatalysisHokkaido University

Kiyotaka Asakura

27 August 2018

XAFS=X-ray Absorption Fine Structure 1

/ a

rb. units

24500240002350023000Photon energy/ eV

X-ra

y ab

sorp

tion

edge

EXAFS (40-1000 eV)XANES

= ln ( I0 / I )

I0 Ix-ray

Local structure around X-ray absorbing atom

No need of long range order.

No need of Vacuum.

Amorphous sample In situ characterization of Materials is possible.

Fourier transformation=> Radial Distribution Function.AgNCO

AgCN

AgSCN

Kag(CN)2

AgSCN

Ag L3-edge XANES.

XAFS in PCCP 1999

1. E. Ramaker, D.; L. Mojet, B.; T. Garriga Oostenbrink, M.; T. Miller, J.; C. Koningsberger, D., Contribution of Shape Resonance and Pt–H Exafs in the Pt L2,3 X-Ray Absorption Edges of Supported Pt Particles: Application and Consequences for Catalyst Characterization. Phys ChemChem Phys 1999, 1, 2293-2302.

2. Mulukutla, R. S.; Asakura, K.; Kogure, T.; Namba, S.; Iwasawa, Y., Synthesis and Characterization of Rh2o3 Nanoparticles in Mesoporous MCM-41. Phys.Chem.Chem.Phys. 1999, 1, 2027-2032.

3. Kuroda, Y.; Kumashiro, R.; Yoshimoto, T.; Nagao, M., Characterization of Active Sites on Copper Ion-Exchanged ZSM-5-Type Zeolite for NO Decomposition Reaction. Phys Chem Chem Phys 1999, 1, 649-656.

2

PCCP special issues3

Recent developments in X-ray Absorption SpetrosocopyEdited by Prof. J.A.vanBokhoven PCCP 2010, 12(21), 5489-5724

5547-5550 Paolo Ghigna, et al. P5701-5706,

Mizuki Tada, Yohei Uemura and Yasuhiro Iwasawa et al. p5562-5574,

Andrew M. Beale*a and Bert M. Weckhuysena

History of XAFS

Year Event

1985 Rõntgen found X-ray1920 First measurement of XAFS(Fricke and Hertz）

1931 R.de L. Kronig XAFS theory Long range order

1930-1958 Shiraiwa

1960 Lytle’s short range theory(

1971 Fourier transformation(Sayers, Stern and Lytle) Phys.Rev.Lett. 27,1204(1971).10.1103/PhysRevLett.27.1204

1970’s SR(SSRL, Hamburg Synchrotron Radiation)1980’s Many SR facilities are constructed

1980’s 3rd Generation SR (APS, ESRF, and SPring-8)Low emittance.

2000’s New 3rd Generation SR( Low energy and low emittance; Diamond, SLS, et al. )

2010’s XFEL starts.

4

Sayers, Stern and Lytle1999

SPEAR in SSRLFrom Synchrotron Radiation ResearchWinick and Doniach Plrenum Press 1982

Comparison between in-lab machine and SR

72 hours / spectrum 30 min /spectrum

5

20000 210000.8

0.9

1.0

1.1

1.2

1.3

1.4

1.5

t

Photon Energy / eV

20000 20100

1.1

1.2

1.3

1.4

t

Photon Energy / eV

1A Rotatory Anode X-ray SR 2.5 GeV- 100 mA

In Lab XAFS machine in early 1980’s XAFS measured on Photon Factory in 1983.

State of Art XAFS techniques High resolution and Sensitivity

Smaller, Faster , Thinner Higher and Sparser) Sample

Smaller nm order is now possible Microbeam, Projection, Pthycography,

Thinner Monolayer – submonolayerSurface Sensitive Techniques.

Faster fs, ps, ns are possible.QXAFS, DXAFS and Pump-Probe XAFS

High energy resolution of Emission. less than 1 eVHERFD-XAS, RIXS,

Sparser ppm, ppb levelFluorescence XAFS

6

M. Tada, T. Uruga and Y. Iwasawa, Key Factors Affecting the Performance and Durability of Cathode Electrocatalysts in Polymer Electrolyte Fuel Cells Characterized by In Situ

Real Time and Spatially Resolved XAFS Techniques. Catalysis Letters,1-13(2014).

Y. Koiked K. Asakura, Structure of low coverage Ni atoms on the TiO2(110) surface - Polarization dependent total-reflection fluorescence EXAFS study. Chem Phys Lett. 421,27-30(2006).10.1016/j.cplett.2006.01.045

11400 11600 11800 12000 122000.002

0.004

0.006

0.008

0.010

0.012

Fluo

resc

ence

/ ar

b. u

nits

E / eV

Pt L3 edge spectra of a 10 ppm Pt complex

Coord. Chem. Rev. 249 65-95 (2005); Eur Phys J-Spec Top 169 207-214 (2009))

State of Art XAFS techniques High resolution and Sensitivity

Smaller, Faster , Thinner Higher and Sparser) Sample

Smaller nm order is now possible Microbeam, Projection, Pthycography,

Thinner Monolayer – submonolayerSurface Sensitive Techniques.

Faster fs, ps, ns are possible.QXAFS, DXAFS and Pump-Probe XAFS

High energy resolution of Emission. less than 1 eVHERFD-XAS, RIXS,

Sparser ppm, ppb levelFluorescence XAFS

7

M. Tada, T. Uruga and Y. Iwasawa, Key Factors Affecting the Performance and Durability of Cathode Electrocatalysts in Polymer Electrolyte Fuel Cells Characterized by In Situ

Real Time and Spatially Resolved XAFS Techniques. Catalysis Letters,1-13(2014).

Y. Koiked K. Asakura, Structure of low coverage Ni atoms on the TiO2(110) surface - Polarization dependent total-reflection fluorescence EXAFS study. Chem Phys Lett. 421,27-30(2006).10.1016/j.cplett.2006.01.045

11400 11600 11800 12000 122000.002

0.004

0.006

0.008

0.010

0.012

Fluo

resc

ence

/ ar

b. u

nits

E / eV

Pt L3 edge spectra of a 10 ppm Pt complex

Coord. Chem. Rev. 249 65-95 (2005); Eur Phys J-Spec Top 169 207-214 (2009))

Catalysts and XAFS

Catalysts are in the form of supported catalystsHighly dispersed metal nanoparticles or single atom.

XRD is not available. XAFS is suitable because it does not require any crystallinity.

in situ measurement is possible.

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FuelFuel cellWater splitting

Exhaustion gas

Catalysts and XAFS

Catalysts are in the form of supported catalystsHighly dispersed metal nanoparticles or single atom.

XRD is not available. XAFS is suitable because it does not require any crystallinity.

in situ measurement is possible.

9

FuelFuel cellWater splitting

Exhaustion gas

H.F.J.van’t Bilk, J.B.A.D.van Zon, T.Huizinga, J.C.Vis, D.C.Koningsberger, and R.Prins,J.Am.Chem.Soc., 107 (1985) 3139.

CORh

Rhx cluster

CO

Corruption of Rh clusters on Al2O3 surface by CO at RT

TEM

UHVIR

In situ measurements.

One can follow the reaction step one by one 11

Mo dimer

3.04 A

2.92A2.61AIwasawa, Y.; Asakura, K.; Ishii, H.; Kuroda, H., Dynamic Behavior of Active Sites of a Sio2-Attached Mo(Vi)-Dimer Catalyst During Ethanol Oxidation Observed by Means of Exafs. Z.Phys.Chem. N. F. 1985, 144, 105- 115.

Time resolved EXAFS12

QEXAFSRapid rotation of Monochromator

• 1 s – 1 min • Not only transmission but also

fluorescence mode measurement Is possible.

DEXAFSEnergy dispersion is made by polychromator q• 1 ms - 1 s

• Only transmission mode

QEXAFS13

A technique that can measure one EXAFS spectrum in a short time ( a few seconds in our system) by sampling signals from ionization chambers and monochromatorcontinuously with scanning the monochromator (on the fly).

Change during the reduction.

XANES FT

14

Every 1min

Every 1min

Slow but high quality and Fluorescence XAFS is applicatble.

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, 7466-7471.

XAFS and IR cross cellBando, 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, 165-171.

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X-rayInfraredThermocouple

Gas injection bulb

Heater

Sample : Ni2P/MCM-4135 mg, 15 mm Φ disk

45 deg tilted against Xray and IR.

Heating system :Heater around the cell

Gas introduction: Gas is introduced

from the 4 ports

Sample

C4H4S + 2H2 → C4H8SC4H8S + H2 → H2S + C4H8

XANES, IR and MS changes during 513 KBando, 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 HydrodesulfurizationConditions. J Catal 2012, 286, 165-171.

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HDSreaction starts

XAFSNi-S

Infrared

Reaction mechanisms

Hydorgenation processes C-S bond cleavage

C-S bond cleavage

H2S

2H2

NiPS Formation processes

Ⅱ : REACTION

2012/Oct/24

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ICEAN2012

THT

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 HydrodesulfurizationConditions. J Catal 2012, 286, 165-171.

Dispersive XAFS@NW2A, Photon Factory(in the cortesy of Dr. Uemura, Prof Nomura and Prof Inada )

A pink beam is dispersed by a polychrometer, which is a bent Si crystal.→ X-ray with several hundreds of eV can be obtained by using position sensitive

detector.→ A XAFS spectrum can be obtained simultaneously.→ The minimum time resolution of the DXAFS system at Photon Factory is 2 ms.

Typical time resolution for in situ XAFS experiments is between several tens and hundreds of milliseconds.

qp

p: from source to polycrometer, q: from polycrometer to focal pointR: bent diameter of polycrometer

19

11560 1160011520

Energy / eV

1.0

0.9

0.8

0.7

11560 11600E/ eV

t

Reversible Reaction Process of Pt followed by DXAFS

Hydrogen reaction on Ptnanocluster

A(d empty state)

B(Pt-Hbondforation)

8

Oxidation Reduction1.0

0.8

0.6

0.4

0.2

0.0

1086420

1.0

0.8

0.6

0.4

0.2

0.0

1086420

B

A

t / st / s

Rat

io o

f spe

cies

900 ms

H

R Pt-Pt =0.254 nmO

Summ

er Challenge in

KEK

A.Suzuki, to be published

Time resolution

30 years ago, before SRSteady state

SR available 30 min

QXAFS 1 s- 1 min.DXAFS 1 ms- 1 s

How to do nano second or less?

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Faster than micro second??A Pump-Probe method

Slow Measurement of fs repeatable phenomena

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X-ray

Pump : Pulse Laser

Probe : Pulse X-raySR （ps-ns)

or XFEL(fs-ps)

XFEL(X-ray Free Electron Laser) (http://www.xfel.net/en/ )

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SACLAhttp://xfel.riken.jp/index.htmlLCLS

http://www-ssrl.slac.stanford.edu/lcls/

PAL-XFELhttp://pal.postech.ac.kr/pale

ng/

European XFEL (Germany) https://lcls.slac.stanford.edu/overview

SASE XFEL SASE=Self-Amplified Spontaneous Emission

China, Swaziland, Germany,Italy …….. Many other XFELs are ready or will be ready.

Pump probe XAFS at SACLA

Experiments at SACLA

SACLA

~10 fs

~50 fs

Sample: 4 mM WO3 suspensionpump laser: 520 mJ/cm2@15 HzX-ray pulse width: 10 fs(FWHM)

Time resolution: 500 fs

sample

x-ray laser

Photoexcitation States of WO3 Chem. Lett. 43 977-979(2014)；Angew. Chem.Int.Ed. 55,1364-1367(2016)；Chemical Communications. 53,7314-7317(2017).

peak A : Edge shift due to formation of W5+ < 1 ps

peak C : decrease of absorption near eg orbitals ~ 200 ps

Three distinct peaks were found in the differential spectra.

peak B which was not found in the previous experiments was

observed.

⇒The spectra were obtained in good S/N ratio

The dynamics of the photoexcited WO3

1 2 3

h

Valence band

1.

2.

3.

The formation of photocarriers

Structural change

Decay of excited states

< 500 fs

k = 0.007 ps-1

k = 0.00056 ps-1Uemura et al. Angew. Chem. Int. Ed. 2016, 55, 1364-

1367

How about much faster processes??

“Real” timing jitters of XFEL

Arrival Timing MonitorKatayama et al. Struct. Dyn. 3, 034301

(2016)

Arrival timing monitor can give precise pictures around time 0

Peak CPeak A

d-orbitals are less filled in less than 500 fs the first transition state might not be the d state. ( W 6s or 6p then relaxed to 5d state. )Or coherent vibration and rapid dephasing

Scheme after the photoabsorption.

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6s or 6p other than 5d or dephasing>2ps-1

Shorter W-O distance

Time resolution

30 years ago, before SRSteady state

SR available 30 min

QXAFS 1 s to 1 min.DXAFS 1 msto 1 s.

How to do nano second or lessPump-Probe femto to nano second.

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Invention of new X-ray source is the key for next jump.

Acknowledgment

Prof Y.Iwasawa(ECU)Prof. Ted S Oyama(Tokyo University)Dr. Kyoko K-Bando(AIST)Dr. Toshihide Kawai(Hokkaido University)Prof. Wang-Jae Chun(ICU)A. Prof. Takahiro Wada(Tokyo Medical and Dental University)Dr. Takeshi Miyamoto(Sumitomo Co.)Prof. Satoru Takakusagi (HU)A. Prof. Hiroko Ariga(HU) Prof. Masaharu Nomura(PF)Dr. Yuichiro Koike(KY Co.)Dr. Kumiko Kinoshita(Fine Ceramic)Prof. Shushi Suzuki(Univ. Nagoya)

FundingNEDO Grant 2001-2004JSPS Grant in Aid for fundamental

research S 16106010 2004-2009GCOE Project Catalysis Driven Innovation

2007-2012MEXT Project Integrated Research on

Chemical Synthesis 2010-2016Catalysis Research Center Collaboration

Project

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