1

High energy X-ray fluorescence analysis

Tokyo University of ScienceDepartment of Applied Chemistry

Izumi NAKAI

Outline

◆ Advantage of the high energy XRF

◆Application

• Laboratory instrument: Food analysis

• Environmental application: Cd Phytoremediation

• Cultural heritage: Provenance of China

• Forensic application: Arsenic murder case

High energy X-rays

U Kα 97.17 U K-edg Eb=115.66keV

0

2000

4000

0 5 10 15 20

Energy/keV

Intens

ity

Overlapping of heavy elements L lines with light elements K lines

Sample porcelain , Source：Mo Kα X-ray 40 kV-40 mA , time:1000sec

Rb Kβ,Y Kα

Sr KαRb Kα

Cu Kα

Ni Kα Pb Lα

Ca Kα

Mn Kα

Ti Kα

K Kα

Fe Kα

Fe Kβ

Sn Sb LaNd

Dy

Tm

BiLu

Positions of the L lines peaks of the heavy elements

Problem of conventional XRF analysis →

2

Fig.

P Ca Mn Zn Br Zr Rh SnCs

NdTb

YbRe

HgAt

U

Zr Rh Sn Cs Nd Tb Yb Re Hg At U

0

20

40

60

80

100

120

0 10 20 30 40 50 60 70 80 90 100

Atomic　Number

Ene

rgy　

(KeV

)Ｋα１

Ｋβ１

Ｌα１

Ｌβ１

X-ray fluorescence energies of K & L lines v.s. atomic number

Z (Atomic Number)

Ene

rgy

/keV

L line for all elements 20 keV > Above 20 keV → K line only →suitable for analysis of elements heavier than Rh Kα (= 20.17 keV )

overlap

◆Advantage of high energy XRF

・High sensitive analysis of trace heavy elements by

excitation of K-shell electrons of heavy elements

・Low absorption effect and high penetration depth

◆ Application field of high energy XRF

Heavy elements ( Lanthanoid elements, U, Nb, Zr, Hf,

W, Cd, Hg etc. ) are important in industry

( high-Tech materials) , environmental science,

geochemistry, archaeology, forensic science for

provenance analyses.

Provenance Analysis

◆Food marketFalse labelingFalse place of origin

◆ Cultural Heritages, archaeology

Place of origin, fake

◆ Forensic analysis

Identification of trace evidence

◆ Approach : an exampleChina ware Raw material → Porcelain StoneTrace element composition of the china ware tells the locality

Role of Heavy Elements

• Cosmic abundances of the heavy elements with atomic number larger than 26 (Fe) are small compared with the lighter elements.

• They exhibit characteristic distribution in earth, because the heavy elements such as rare earth and U often posses large ionic radii and high oxidation states.

• The trace elements often substitute for major elements in crystalline phase, whose manner is largely affected by the nature of the elements such as the ionic radii, oxidation state as well as the PTC condition.

Good fingerprint elements

→ High energy SR-XRF analysis

3

Laboratory instrument Epsilon 5 (PANalytical)

sample

Ge-SSD

2nd target

Gd X-ray

9

X-ray tube: Gd 100kV

Detector: Ge-SSD

Optical system: 3D polarization optics with secondary targets

Wheat flour

10

Domestic 12

Imported (U.S.A. Canada, Austlaria ) 10

Mixture 14

Total 36 samples

80 % of wheat flours is imported in Japan

Domestic product → expensiveImported product → cheap

Provenance analysis of foods

Sampling method

Dry(85 ℃、4hr)

Cooling to R.T.

Disk

Plastic cup

Mylar film(2.5 μm)

paper

Disk

Plastic plate

Disk 20mmφ、9 tonf/cm2 、5min

11

0.03

0.06

0.09

0.12

0 5 10 15 20

Br

Rb

Thickness (mm)

8 mm(3.0 g)

XRF intensity as a function of thickness

Measurement

◆1.5 g (4mm thickness)

◆Normalization by

Compton scattering

A comparison of measurement time

Meas. time 1800s<

Sample： NIST SRM 1567a (Wheat Flour)Disk： 20 mmφ2nd target：Al2O3

12

Energy (keV)

600 s1800 s2400 s3600 s

7200 s

9000 s

10800 s

4

Al

TiFe

Ge

Sample： NIST SRM 1567a (Wheat Flour)Disk： 20 mmφ2nd target：Al2O3 Ti、Ge、Mo、Al 2O3

13

Energy (keV)

Al2O3、Ag、Mo、Zr、Ge、Fe、Ti、Al、CsI、Rh

A comparison of secondary target Quantitative analysis

Calibration curve

NIST SRM 1570a Spinach LeavesNIST SRM 1515 Apple LeavesNIST SRM 1573a Tomato LeavesNIST SRM 1567a Wheat FlourNMJ CRM 7501-a (Cd 1) riceNMJ CRM 7502-a (Cd 2) riceNIES No.10-a (Cd Low) riceNIES No.10-b (Cd Medium) rice

Selection of standards

sample 20 mmφ、1.5 g2nd target Ti、Ge、Mo 1800 s

Al2O3 3600 s

Meas.con.

17elements

Na, Mg, Al, P, S, Cl, K, Ca, Mn, Fe, Cu, Zn,

Br, Rb, Sr, Mo, Cd

14

R² = 0.9929

0

0.05

0.1

0 0.45 0.9

R² = 0.9987

0

0.0015

0.003

0 6 12

R² = 0.9973

0

0.035

0.07

0 45 90

R² = 0.9994

0

0.005

0.01

0 7 14

R² = 0.9916

0.1

0.3

0.5

1000 2000 3000

R² = 0.9946

0

0.0007

0.0014

0 3.5 7

Calibration curves for quantitative analysis

Concentration (ppm)

Cu

Br Rb Mo

Zn

15

K17 elements (R2 = 0.97~ 1)

Concentration (ppm) Concentration (ppm)

Concentration (ppm) Concentration (ppm) Concentration (ppm)

Accuracy Comparison of the data

sample (Wheat Flour) NIST SRM 1567a

Deviation

( ) [ ] [ ][ ] 100% ×

−=

certified

certifiedmeasured

M

MMD

[M]measured：measured value (ppm)[M]certified：certified value (ppm)

The method is reliable

(n=3) 16

Meas. NIST D(ppm) (ppm) (%)

Na 6.25 6.1±0.8 2.5Mg 387 400±2 3.3Al 5.19 5.7±1.3 8.9P 1340 1340±6 0.01S 1450 1650±2 12Cl 572 565 1.2K 1337 1330±3 0.5Ca 190 191±0.4 0.5Mn 8.5 9.4±0.9 10Fe 13.4 14.1±0.5 5.0Cu 2.13 2.1±0.2 1.4Zn 11.8 11.6±0.4 1.7Br 6.03 6 0.5Rb 0.673 0.68±0.03 1.0Sr 0.797 ? ?

Mo 0.485 0.48±0.03 1.0Cd 0.0267 0.026±0.002 2.7

5

Detection limit

LLD

t

I

I

CLLD BG

net

3=

C ：Analytical data (ppm)Inet ：Peak Intensity (cps/mA)IBG ：B.B. Intensity (cps/mA)t ：Measurement time (s)

LLD of analyzed elements

XRF analysis of heavy elements with sub ppmsensitivity

17

Sample (Wheat Flour) NIST SRM 1567a

LLD LLD(ppm) (ppm)

Na 5.05 Fe 0.085Mg 69.3 Cu 0.031Al 0.11 Zn 0.058P 9.20 Br 0.090S 3.90 Rb 0.39Cl 2.08 Sr 0.11K 0.67 Mo 0.079Ca 0.37 Cd 0.0061Mn 0.11

Application to Practical samples

(Domestic 12、Imported 10、mix 14)

18

Con

cent

rati

on (

ppm

)

10 2

10 3

10 4

10 1

10 0

10 -1

10 -2

elements

DomesticImported/mix

Na

Mg

Al

S Cl K

Ca

FeBr

RbSr

Mo

Cd

※ P、Cu、Zn：n.d.

Ca、Fe、Br、Rb、Sr、Mo

PC1 (50.9 %)

Japan(12)、Imported(10)、mix(14)

-1

0

1

-1 0 1

RbSr

Br

Ca

FeMo

Principal component analysis of the analytical data

PCA plot using the concentrations of 7elements

Factor loading plot-3

0

3

-3 0 3

PC

2(2

9.3

%)

JapanImportedMix

Characteristics of SR-XRF

6

ＳＰｒｉｎｇ－８

Construction from 1991 Public use since 1997

SPring-8 BL37XU

detecor

Sample on XYstage

X-ray

K-Bmirror

XY slit (0.2 x 0.2 mm)Si 111 Monochromator

XY slit (0.15 x 0.15 mm)K-B mirror

Sample

53 m

In-vacuum undulator

X-ray energyAs： 12.8keVCd: 37.0keV

μ-XRF, μ-XANES

Beam siz: ca. 1 μm

- BEAMLINE DESCRIPTION -The light source : In-vacuum type undulator

(Period length : 32 mm, the number of period : 140)Monochromator : Double-crystal monochromator

located 43 m from the source

fused quartzplatinum coated

250 mm100 mm0.8 mrad

12.8 keV37 keV[1]

fused quartzplatinum coated

100 mm 50 mm2.8 mrad

MaterialSurfaceFocal length (1st mirror)

(2nd mirror)Average glancing angle

Table Details of focusing optics by K-B mirror

- BEAMLINE DESCRIPTION -The light source : In-vacuum type undulator

(Period length : 32 mm, the number of period : 140)Monochromator : Double-crystal monochromator

located 43 m from the source

fused quartzplatinum coated

250 mm100 mm0.8 mrad

12.8 keV37 keV[1]

fused quartzplatinum coated

100 mm 50 mm2.8 mrad

MaterialSurfaceFocal length (1st mirror)

(2nd mirror)Average glancing angle

fused quartzplatinum coated

250 mm100 mm0.8 mrad

12.8 keV37 keV[1]

fused quartzplatinum coated

100 mm 50 mm2.8 mrad

MaterialSurfaceFocal length (1st mirror)

(2nd mirror)Average glancing angle

Table Details of focusing optics by K-B mirror

Arabidopsis halleri, Cd and Zn hyper-accumulator

and Cd in Rice

Micro X-ray fluorescence imaging and micro X-ray absorption spectroscopy of cadmium hyper-accumulating plant, Arabidopsis halleri ssp. gemmifera, using high-energy synchrotron radiation

Journal of Analytical Atomic Spectrometry, 23, 1068-1075 (2008)

N. Fukuda, A. Hokura, N. Kitajima, Y. Terada, H. Saito, T. Abe and I. Nakai.

Application of SR-XRF to in vivo analysis of Cd in biological sample

Study of hyperaccumulator plants of Cd

7

Cd isolation

-Cd

Cd

CdCd

Cd

Cd

Cd

Cd

Cd

Cd

Contaminated soil

Cd. ...

.. ...

Phytoremediation

plant remediate

Green technology by plantMerit：no damage,low cost

preservation of surfaceetc…

Element conc./ ppm plant

As 22,630 Pteris vittata L. (モエジマシダ）Cd 11,000 Athyrium yokoscense ( ヘビノネゴザ）

Pb 34,500 Brassica juncea (カラシナ)*1 L. Q. Ma, et al., Nature, (2001) , 409, 579.

*1

Some specific kinds of plants are known to be heavy metal hyperaccumulator

ash

Phytoremediation is a technology that uses plants to remove, destroy, or sequester hazardous substances from the environment.

Arabidpsis halleri ssp. Genmifera (ハクサンハタザオ)

Arabidopsis halleri is known as a Cd and Zn hyper-accumulator, which contained more than 9000 mg/ kg

Cd and Zn.

Application example 2: Cd hyper-accumulating plant, Arabidopsis halleri ssp. Gemmifer

HM

1: absorption of heavy metal

HM HM

HM

HM

HM3: accumulation

HM

HM

HMHM

2: transportation

Hyperaccumulation

HMHM

HM

HMHM

8

Application of SR X-ray analyses

・Two dimensional multi-elementnondestructive analysis in cell level→ μ-XRF imaging

・ in vivo chemical state analysis of metals in the plant→ X-ray absorption fine structure (XAFS)

analysis

・chemical state analysis in cell level→ μ-XANES

Instrument ~Spring-8 BL37XU~

SDDSample

Acrylic plate (1 mm thick)

X-ray

検出器

KEK PF BL12CAs K-edge (11.863 keV)Si(111) double crystalFluorescence mode19elements-SSD

in vivo XAFS

X-ray

SSD

XAFS analysis

vertical slicer (Model HS-1, JASCO Co.)

200μm thick

Mylar film Plastic plate

X-ray

moist unwoven paper

Sample preparation for microbeam analysis

freeze dry of frozen

9

XRF imaging of a leaf of A. halleri ssp. Gemmifera.

X-ray Energy : 37 keVBeam size : 50 μm× 50 μmMeasurement points : 60 point×100 pointmeasurement time : 1 sec/point

Zn

2063

0

Rb

13

0

Cd

704

0

Sr

38

0

μ-XRF imaging of a trichome taken from a leaf.

Zn

199

0K

17

0Sr

19

0Cd

101

0 Ca

60

0

X-ray Energy : 37 keVBeam size : 3 μm× 3 μmMeasurement points : 59 point×226 pointmeasurement time : 0.5 s/ point

100 μm

Trichomes are epidermal hairs present at the surface of leaves of A. halleri, and their functions are thought to be an exudation of various molecules.

Cd K-edge μ-XANES

スペクトルの取得に成功！

ZnCd

V

H50 μm

CdCd KK--edge edge μμ--XANESXANES

Cd bonds to O like Zn

CdCd--SS

CdCd--OO

CdCd--NN

～XANES～

curve

flat

* I. J. Pickering, et al., Biochim. Biophys. Acta, 1429, (1999), 351.** G. Sarret, et al., Plant Physiol., 130, (2002), 1815.

low high

Cd-Ac

CdS

CdO

(Im)6Cd(NO3)2

Cd2+ aq.

MT-Cd

Pc-Cd

(i)

(iii)

(ii)

(i)

(iii)

(ii)

26.672

Energy (keV)

26.772

Nor

mal

ized

Int

ensi

ty (

a.u.

)

26.72226.697 26.747

Beam size: 1.3 μm (V)×3.8 μm (H)Energy step: 1 eVDwell time : 1-4 s/point

Application of high energy X-rays (116 keV)

10

Si(400)MonochromatorSR

slit

GeSSD

I.C.

ＸYステージ

sample

Eliptical multipole wiggler (Gap:160～25.5 mm)Excitation energy:116 keV (100-150 keV)Beam size：1～0.1 mm2

PC

BL08W （for High-energy inelastic scattering experiments)

Experimental setup for high energy XRF

MCA

0

500

1000

0 10 20 30 40 50 60 70 80

X-ray energy (keV)

Inte

nsity

(Cou

nts/

1000

sec)

W

Lu

YbEr

Ta

Tm

Ho

Hf

Gd

Bi

Dy W KβSm

La

Nd

EuTb

Pb*

Ta Kβ

Hf Kβ

Lu Kβ

Ce

Pr

Ba

Cs

XRF spectrum of NIST SRM612 glass: 61 trace elements in 50ppm level(*scattering)

Rb

Nb

CdPb

Ca

Sn

Mo

In

Ag Sb

Te

0

500

1000

1500

0 10 20 30 40 50 60

X-ray energy / keV

Inte

nsit

y / c

ount

s

W Kα1,2

Hf K1,Yb Kα1,2

Dy Kα1,2

Er Kα1,2

Ba KαBa Kβ

Nd Kα

Nd Kβ

Sm Kα

Ce Kβ

Gd Kα

Ce Kα1,2

La Kα

Cs Kα

Fe Kα

Fe Kβ

Mn Kα

Pb Lα,β

Sr Kα

Nb Kα

Ba esc.

Rb Kα,β

Zr Kα,β

XRF spectrum of JG1 excited at 116keV for 1000sec.

Contents/ ppm Ipeak Iback MDL/ppm

Fe 2.02a) 1557 366 0.097a)

Rb 181 577 281 30.8

Sr 184 719 258 19.2

Zrb) 108 395 293.5 54.7

Cs 10.2 280 181 4.2

Ba 462 7205 354.5 3.8

La 23 535 355.5 7.2

Ce 46.6 520 86 3.0

Nd 20 862 154.5 1.1

Sm 5.1 136 45 1.1

Gd 3.7 108 42.5 1.1

Dy 4.6 110 41 1.3

Er 1.7 86 51.5 1.1

Yb 2.7 125 61 1.0

Hf 3.5 268 98.5 0.6

W 1.7 737 199.5 0.1

MDL for JG1 sample

11

0.001

0.01

0.1

1

10

0.01 0.1 1 10

Metal concentration (ng)

Nor

mar

ized

net

inte

nsity

(I L

u/I G

d)

Lu

Calibration curves for Lu using K-lines XRF spectra

・肥前(Arita) a加賀（Kutani)

・福山姫谷(Himetani)

･有田

･伊万里、嬉野

･波佐見

Colored Porcelain Since 17th Century

Provenance analysis of Old-Kutani China waresbased on the information of heavy elements

obained by high energy XRF

・Old Kutani china wares: produced in the late 17th century in Japan. After half a century, the kiln was suddenly closed. Pottery from this early period is extremely precious.

・However, there is a possibility that the Old Kutani might come from Arita, another famous production place of porcelain in Japan.

・Identification of Old Kutani and Arita is an important and mysterious problem in Japanese art history.

・This is the first nondestructive analysis of museum grade samples of Old Kutani.

)とうP

Kutani

Himetani

Arita

Raw Material

Porcelain Stone tells the Locality

12

Samples

◆Fragments of porcelain excavated at each

old kiln of Kaga, Arita, and Fukuyama.

Kutani: 121 Arita: 57 Fukuyama: 10

◆Museum grade samples which are thought

to be original： 6

0

1000

2000

3000

0 10 20 30 40 50 60 70Energy / keV

Inte

nsit

y/co

unts

Fe

Pb

Rb

Y

La

HfW

Zr

Nd

Ce

Cs

Er

Gd

Sm

Dy

Yb

Sr

Ba

Se

XRF spectrum of fragments of china ware excavated from Old Kutani kiln

13

H 0 1H 0 2H 6 0H 6 4H 1 4H 3 3H 5 4H 5 2H 4 1H 5 9H 2 8H 6 3H 2 9K 0 5K H 8H 3 5H A 2K 1 7K 1 8K 3 2K 1 0 3H 4 6H 0 3H 5 7H 3 1H 6 8H 0 7H 5 5H 0 9H 1 6H 2 7H 5 6H 6 8H 2 3H 4 0H 1 5K M 1K 1 2K 1 4H 3 4H 5 1H 6 2H A 5K M 2H 0 4H 6 7H 1 3H 3 2H 6 1H 6 6H 6 5H M 1H M 3H M 5H M 6H M 8H M 9H M 2H M 4H M 7H M 1 0K 0 6K 1 3K 1 9K 2 1K H 5K 2 0K 0 8K 2 6K 2 8K H 1K H 3K 1 5K Y 2K 1 0 5K N 1H 1 0H 3 9H 5 8H 5 3H 3 0H A 6H 1 1H 1 2H A 1H 4 7K 2 7K 1 0 9K 5 2K 4 7K 5 1K 5 6K 6 0K 5 9K H 7H 4 3K 3 4K Y 2K Y 3K 5 3K H 1K 0 7K 0 9K 1 6K 2 3K M 1K 3 7K M 2K 4 9K 2 2K 4 8K 3 3K 5 0K 5 5K 3 9K 2 5K 1 0 1K 2 9K H 3K 3 8K H 5K 3 5K 4 4K H 8K Y 3H A 3

0 5 1 0 1 5 2 0D i s t a n c e

Cluster analysis of fragments of china wares using normalized XRF peak intensities of Ba, Ce, Nd

Kutani

Kutani & Arita

Fukuyama

Arita

Ba/Ce-Nd/Ce plot

0

4

8

12

16

0 0.2 0.4 0.6 0.8 1 1.2Nd/Ce

Ba/

Ce

原明窯小溝上百間窯ダンバギリ窯窯の辻窯猿川窯長吉谷窯下白窯柿右衛門窯鍋島藩窯不動山皿屋谷二号窯吉田二号窯三股古窯永尾本登窯辺後の谷窯三股新登窯福山姫谷窯九谷一号窯九谷二号窯吉田屋窯若杉古窯八間道耳聞山今九谷山代

KutaniKutani

AritaArita

FukuyamaFukuyama

Provenance characterization of museum grade samples

0

4

8

12

16

0 0.2 0.4 0.6 0.8 1 1.2Nd/Ce

Ba/

Ce 有田、伊万里 嬉野、波佐見

福山姫谷 加賀古九谷大皿（釉有） 古九谷大皿（黒紫）古九谷大皿（釉有白） 古九谷大皿（黄）今九谷大皿（釉有白） 今九谷大皿（釉有白）古九谷中皿（糸切） 古九谷中皿（割れ目）古九谷中皿（釉有） 古九谷中皿（釉有白）古九谷中皿（釉有白,裏） 古九谷中皿（赤）古九谷角皿（釉有） 古九谷角皿（釉有）古九谷角皿（青） 古九谷角皿（金）古伊万里（糸切） 古伊万里（釉有）古伊万里（釉有） 梅樹七宝図(糸切、釉有)梅樹七宝図(縁、釉有) 梅樹七宝図（白釉）青九谷椿文(糸切) 青九谷椿文（縁）

KutaniKutani

AritaArita

FukuyamaFukuyama カレーPaper Cup

Curry Rice

CookingAs2O3

Arsenic Murder caseArsenic Murder case

DateDate: July 25 , 1998

Acute Arsenic intoxication : Acute Arsenic intoxication : Death 4 Injured 63

Place: Festival Site at Sonobe , Wakayama Pref. JAPAN

Forensic application

14

factory・production・purification

product As2O3plasticcontainer

paper cup

currypoisning

Priciple of identification : arsenic trioxide →heavey elements impurity: Sb, Bi, Sn, Mo

mine

ant insectide

business

Ｓ＆Ｗ Gunshot Residue

ＳＰｒing-８ ＢＬ０８Ｗ

Characteristic element: Ba,Sb, Pb

Ba

SbPb Pb

High energy SR-XRF characterization of trace gunshot residue

Forensic application

0 20 40 600

500

1000

1500

WTaSnNb

ZnFeTi

coun

ts

Energy(keV)

A

0 20 40 600

500

1000

Nb

Zn

Ba

Ti

Energy(keV)

B

0 5 10 15 200

5000

10000

SiAlFe

Ti

Cou

nts

Energy(keV)0 5 10 15 20

0

5000

10000

Al

Ti

Cou

nts

Energy(keV)

EPMA EPMA

Ninomiya(２００４）

High energy XRF characterization of trace heavy elements in white car paints (paints A & B) compared with X-ray microprobe (bottom) Conclusion

Limitation of the SR-XRF１．Microbeam analysis

i) the thickness of the sample should be in the order of beam size

→ preparation of thin sample is not easy

ii) it takes long hours to carry out two dimensional mapping

because of large numbers of measurement points

2. Low excitation efficiency for light elements

3. Special efforts is necessary to carry out quantitative analysis

4. Sample damage should be considered if you use brilliant Undulator SR Source or white X-ray radiation. Especially, care must be taken about photo-reduction/oxidation of the component elements.

15

Attractiveness of (SR)-XRF

１．Nondestructive analysis, multielemental analysis

2. Two dimensional resolution

3. Easy to carry out the analysis and easy to understand the results

4. Basic optical system for EDS analysis is simpleSR → Monochromator → sample → detector

５．We can analyze almost any sampleｓ

size → from cell level to sculpture, paintings

in situ、 in vivo、 in air at any temperature

6. Information

concentration： major（％）, minor, trace（ppm) elements C ～Na ～ U

distribution: from nm level to cm level

chemical state ( oxidation state, local structure) C ～ Si ～ U

７．Multiple SR-X-ray analysis: combination with X-ray diffraction and XAFS

Especially, high energy XRF is attractive in

・High sensitive analysis of heavy elements

・Application fields

Environmental, food, archaeological, forensic, geo- & cosmochemical analyses.

References for High-Energy XRF

・Use of highly energetic (116keV) synchrotron radiation for X-ray fluorescence analysis of trace rare-earth and heavy elementsI. Nakai, Y. Terada, M. Ito, Y. Sakurai,J. Synchrotron Rad., 8, 1078-1081

(2001）

・I. Nakai, 5.5 “High Energy X-ray Fluorescence” in X-ray Spectrometry : Recent Technological Advances, Ed. by K. Tsuji, J. Injuk, R. V. Griken, John Wiley & Sons, Ltd., pp.355-372 (2004)