IAEA Regional Training Course , 8-12 November 2010

Nano structured materials

Multilayer Films,

Polycrystalline,

Nanocomposites,

Patterned structures,

Bulk structures,

Liquid crystals,

Biological samples,

Fractals,

Gels,

and etc.

Monochromatic

X-RaysScatte

red

X-Rays

“When scientists have learned how to control the arrangment of matter at a very small scale, they will see materials take an enormously richer variety of properties” Richard Feynman (1959)

High flux, more intensed x-rays

Widely used flux, conventional x-rays

1013 photon/s/mm2

108 photon/s/mm2

Diluted -I

Diluted -II

Densed -I

Densed -II

LamellarDifferent formed aggregats can be investigated

The other densed systems

03.01 -20.07 2009

k

k’

-k

q2ө

q, X-ray scattering vector

q= k´-k

|q|=2 k sin

q= 4 sin /

I (Scattering intensity)

q (Å-1)

I (Scattering intensity)

q (Å-1)

SWAXS (Small and Wide Angle X-Ray Scattering) Analizleri

A(q)

= Ae (r) exp(-iq.r) dr

Scattered wave amplitude

(r)

= [A(q)/Ae] exp(iq.r) dq

Radial electron density

Fourier T.

I(q)= |A(q)|2

= Ae2 | (r) exp(-iq.r) dr |2

= P(r) exp(-iq.r) dr

Scattered wave intensity

P(r)

= (u+r) (u) du

= I(q) exp(iq.r) dq

Distance distribution function

Fourier T.

Reciprocal space Real space

The followed process to determine structures is used

Measuring data

Determining of structural parameters R, M, V etc.

Defining model structure in real space and for this purpose using

other collaborative techniques

Construction of the model in q space and fitting of the

experimental and theoretical results

In addition to SAXS technique other techniques are:

SANS ( Small angle neutron

scattering)

XAFS (X-ray Absorption

Fine structure),

XRD (X-ray Diff.) and

Microscopy techniques.

More sensitive and recordable structural results can be obtained by this combination .

1. region 2. region 3. region

I(q) = N [F(q)]2 S(q)

q

I Experimental curve

P

q

Particle Form Factor P(q)= F(q) 2

S

q

Solution Structure Factor

I(q) = N [P(q)]

I(q) = N1 [P1(q)]+ N2 [P2(q)]

I(q) = N g(R) [P(q)] dR Dilute polydisperse

Dilute two type particles

Diluted identical

It defines the relatonship between

the positions of the particles

F(q)= 3V (1-2) [ sin(qR) – qR cos(qR) ] / (qR)3

22~26°~26°22~18°~18°3.2Å3.2Å4.8 Å4.8 Å

sample: lactose powdersample: lactose powdersample-detector distance: 29.5 cmsample-detector distance: 29.5 cmactive length of detector ~ 5 cmactive length of detector ~ 5 cm1024 pixels 50 µm/pixel1024 pixels 50 µm/pixel

WAXS

Calibration of the q-scale (WAXS) with p-Br-BA powder:

Primary beam Primary beam (attenuated)(attenuated)

FWHM ~ 350 µmFWHM ~ 350 µm

2665 Å2665 Å800 Å800 Å

11Å11Å

sample: Lupolensample: Lupolensample-detector distance: 28 cmsample-detector distance: 28 cmactive length of detector ~ 5 cmactive length of detector ~ 5 cm1024 pixels 50 µm/pixel1024 pixels 50 µm/pixel

center of incident center of incident primary beamprimary beam

22~8°~8°

SAXS

Calibration of the q-scale (SAXS)

with Ag-behenate powder:

Lamellar d-spacing: d = 58.38 Å

Diluted systems-I

Protein or polymer solutions, etc.

First determined structural information - Radius of gyration,

- Mass, volume and shape

I Guinier region

. q(nm-1)1/R

I(q) =I(0) exp(-R2q2/3)

q2

ln I

tan = -R2/3

Guinier line

glass NoncrystallizedaggregationsNanocrystalsNanocrystals Different electron densities

R<R0 R=R0 R<R0

Before cystallization After the cryst.

Spherical nano crystals embeded SiO2

r 2 (r) d3r

R2 = (r) d

3r

____________  R= (a2+b2+c2)/5

   ____ R= (3/5) r = 0.77 r

Radius of gyration

Elipsoid

a,b,c elipsoid axes

Sphere

r, radius

Guinier law

(q0)

Porod law (q)

lim I(q) q4 = constant

lim I(q)= 2 (1-2)2 S / q4

S, surface area

I(q)q4

q (Å-1)

Porod region

Kratky plots Q = V <2>

Fluctuation in the electron densities

V Total volume causing the scattering

Sample: Amorph and crystalline regions in the structure

Two phase polymers

Q = V (k-a)2 ak

k , a electron densities of the phases

a , k volume fractions of the phases

Kratky plots with Porod law

QQ

qq (nm) (nm) -1-1

II .. qq

2 2 (n

m)

(nm

) -2

-2

InvariantInvariant

Lamellar StructuresI

q

The positions of Bragg peaks for

h = 1, 2, 3 give the lamellar distance (1/d)

If we look through the perpendicular direction of the lamelar structure, we may define crystallographic order in SAXS range. In this case, by using scattering intensity ratios and peak positions, some scattering rules ( for hexagonal, cubic etc.) controlled and compaired to obtain the real phases.

0.0 0.1 0.2 0.3 0.4 0.50

20

40

60

80

I(q

)

q

0.0 0.1 0.2 0.3 0.4 0.50

20

40

60

80

I(q

)

q

0.0 0.1 0.2 0.3 0.4 0.50

20

40

60

80

I(q

)

q

Im3m P-surface Pn3m

D-surface Ia3d G-surface

Some ordered cubic morphologies

Figures, H. Amenitsch, SR School-ICTP

?

Lamellar fluid Hegzagonal struct.

I.

II.

III.

lamhex

According to the observed q ratios

(1) Periodic structure： 1 : 2 : 3 : 4…; (2) Cubic： 1: 2 : 3 : 4 : 5 …. ; (3) Hegzagonal 1: 3 : 4 : 7 : 9 : 12

PS-b-PEO Co-polymer phase transition

Photonic crystals

Blue Light blueHeating

Interplanar distance is increasing with increasing temperature

www.hecus.at 23

SWAXS scanning of phase transitions

300 s / Frame

SAXS

WAXS

20°

45 °

Sample rotation enhances signal-noise ratio

Spin-cap (rotating capillary)

300 s / Frame

ln I(q)

q (Å-1)0.05 0.10 0.15

ln I(q)

q (Å-1)0.05 0.10 0.15

ln I(q)

0.05 0.10 0.15q (Å-1)

ln I(q)

-2.50 -2.00 -1.50 -1.00 ln q

Guinier

Porod

Slope

Shape reconstruction

Hydrophillic(repulsion)

Hydrophobic (attraction)

shell

core

Volume hight and base area of the cone were determined beside of packing parameter

t

Rs

Rc

ρc

ρs

ρç

t = thicknes of the shell

Rc = core radius

Rs = t + Rc

ρc = core electron density

ρs = shell electtron density

ρç = solution electron density

pH controls charge level and if the misel size increase s, electrostatic repulsion becomes effective.

A serial research on pH and temperature dependent-water soluble diblock copolymers[2-(dietilamino) etil metakrilat]-b-[2-(dimetilamino) etil metakrilat] (DEAn-b-DMAm)

DEAn-b-DMAm diblock copoylmers are stable (n/m=1/2) in misellar forms at 23C ve pH=7,7. size distributions are narrow and forms are spherical.For T=22,0-25,5C, pH=7,6-8,0 and n/m=0,25-0,73 values, misel numbers per unit volume, misel sizes, shell thickness, core radius and densities have been determined by SAXS analysis.

13 nm

Y11, ……, Y20

Y9,Y10

Y9,Y10

Cubic structures occured by DNA and peptid connected spherical gold nanoparticles

H3

liquid paraffin, non-ionic surfactants (Brij 72 and Brij 721P) and/or pure water

Formulation Liquid Parafin (%w/w)

Brij 721 P/ Brij 72 (3/1) (%w/w)

H2O (%)

A3 70 30 -H3 - 30 70L2 6 31 63F1 40 10 50

AFM View

TEM View

[D.I. Svergun, Biophysics J. 1999, 76, 2879-2886]

Ferroelectric thin films, P.C. Mclntyre Res. Group, Stanford

Photovoltaics, H. Kurz, Inst. of Semiconductor Elect. Germany

Multilayered Al-Si Porous thin films, C. Orilall , Cornel Univ.

Nonhomogen dielect. (sculptured) thinfilm, STF, A. Lakhtakia, Penn State

SrGa2S4:Ce thin-film, K. Tanaka, NHK Lab. Japan

Ultra-thin solid oxide fuel cell,F.B. Prinz ,RPL Stanford Engineering

400 Å

400 Å

400 Å

400 Å

Sample I (7) Sample II (8)

65 Å 55 Å

55 45

45 40

20 mol%

24

27

33

21 mol%

24

30

35i Al Ga As

n Ga As

n+ Ga As

n+ Ga As

GaAs , a= 5.65 Å, = 5.32 g/cm3

AlGaAs, a= 5.66 Å, = 3,76 g/cm3

da dac dc

k is decay constant (interfacial area) for a two phase system.It depends on the total inner surface (S) and the mean-square electron density fluctuations

Qinvariant

It has the dimention of a resprocal volume

Total irradiated volume

Volume fractions

Mean sizes of the planar aggregations in the content of the sample I and II are 198.09 and 121.67 Å , respectively.

d(Å)Sample I (7) d(Å) Sample II (8)

330.00 202.70

184.73 116.40

136.59 80.24

104.70 61.00

82.6770.5960.4152.79

49.8742.1637.4030.35

R( Å)Sample I

R( Å)Sample II

5.3230.7756.4179.48100.02125.64184.63217.94258.97317.95371.80425.64453.85

6.4435.4262.7983.72122.36161.10194.81223.79262.43281.75

Summary

Analysis of total scattering gives valuable insight in the structure-properties relationship

High resolution instruments open the door to medium-range order investigations

Usage of collaborative techniques always preferable to reach more detailed knowledge.

www.hecus.at 42

+

2. BP

1. BP

SB

LS

PB

f

i

- tarama

GISAXS0.2- 0.6 ⁰

Düzgün yönelmiş tabakalar İzotropik

lipozom

SAXS ile algılanan nano-oluşumlar (1-100 nm)

WAXS ile algılanan nano-oluşum iç yapıları ( 1-10 Å)

SAXS ile elde edilen bilgiler:*Kesikli çizgilerle gösterilen elektron yoğunluk farklarının yüksek olduğu nano oluşumların şekli/şekilleri

* Nano-oluşumların ortalama büyüklükleri

*Nano-oluşumlar arası ortalama uzaklık ve uzaklık dağılımları

*Birim hacimdeki nano-oluşum sayıları v.b. bilgiler.

Lc : correlation distances

Lc

Plaka formu için yapısal bilgiler

İkili uzaklık dağılımları

Polimer içine dağılarak bulundukları genel malzeme ortamının elektron yoğunluğunu artıran moleküler saçaklanmalar

Bütün verinin GNOM programı ile arıtılması

F o l i e : S A X S 6 . d o c

F o u r i e r T r a n s f o r m a t i o n o f P a r t i c l e S c a t t e r i n g C u r v e

I h p r

h rh r d r

40

s i n ( )

I ( h )

h p ( r ) r

p ( r ) . . . P a i r - D i s t a n c e D i s t r i b u t i o n F u n c t i o n w i t h i n t h e P a r t i c l e r

a v e r a g e d o v e r a l l p a r t i c l e o r i e n t a t i o n s

q u a l i t a t i v e i d e a s o n s i z e a n d s h a p e