Wim Bras DUBBLE @ ESRF Netherlands

Wim Bras
DUBBLE @ ESRF
Netherlands Organisation for Scientific Research
(NWO)
Outline
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Short introduction synchrotron radiation
European Synchrotron Radiation Facility
DUBBLE
Examples of research on Dubble
Synchrotron as X-ray source
Bending magnet
Electron orbit
What is the advantage of SR?
Number
of photons
Wavelength (Å)
10000
1000
100
10
1
0.1
1014
•
•
•
•
1013
1012
1011
1010
109
108
107
1 eV
10 eV
100 eV
1 keV
10 keV 100 keV
Energy
sunlight
conventional
X-ray generator
High flux
Continues spectrum
Good collimation
Beams 1 – 300 micron
Scheme beam line
storage
ring
experiment
Control cabin
Optics
monochromator
focussing
• These labs are set up as user facilities
• They are relatively large scale
• Belgium and the Netherlands have
made the choice to participate in
international facilities
• However….
Once upon a time in the
Watergraafsmeer
Nomen est omen???
1979
NWO and synchrotron radiation
Daresbury also birth place of
Lewis Carrol
Alice en the
Cheshire cat
Daresbury lab in Cheshire
- About 30 years ago
ZWO/NWO started participation
in Daresbury Lab (UK)
- About 15 years ago transfer to
ESRF
-The Netherlands has a strong
SR user community
European Synchrotron Radiation Facility
Grenoble France
European Synchrotron Radiation Facility
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∼ 50 beam lines (= experimental set ups)
∼ 25 different techniques
6 days/ week, 24 hours/day
270 days/year (minus strike days, after all it is
France….)
• ∼ 1500 publications/year
270 meter
the ESRF
Many different experiments
Protein crystallography
About 25% of the beam lines
About 35% of publication output
Crystal distortions due to high
(30 Tesla) magnetic fields
Spider silk
Chocolate butter crystallisation
Dutch ESRF participation
• 6% of the experimental time on public beam
lines is for the Benesync consortium (50/50
Be/Nl)
• This is not sufficient for the Dutch/Belgian
demand for some techniques
• Two ‘own’ beam lines
• DUBBLE (part of the Dutch research
infrastructure)
DUBBLE: 5/6/2000 the official opening
The ministers
The financing
The workers
DUBBLE research areas
surfaces
Geology/surface
instrumentation
pollution
catalysis
surfactants
polymers
biological/medical
structure
foods
colloids
Two beam lines and techniques
on DUBBLE
• Extended X-ray Absorption Fine
Structure spectroscopy
(EXAFS/XANES)
• Small and Wide Angle X-ray Scattering
(time-resolved SAXS/WAXS)
3-4 user groups/week
At present 70 – 80 publications/year
X-ray scattering
detector
1 – 8 meter
sample
Diffracted X-rays
X-rays
λ = 2d sin θ
θ small
d large
SAXS/WAXS
1 limit q → 0
electron density contrast
density fluctuations
1
2
3
4
1
5
2 Guinier range
particle size
3 particle shape
4 Porod range
particle surface
500 nm
0.2 nm
5 Intermolecular/atomic
ordering
X-ray scattering and diffraction
• Combined SAXS-WAXS experiments
• WAXS crystalline structure
• Small angle: shape and size of clumps of
atoms
• SR
not only static
also time-resolved
• 0.4 – 200 nm ‘visible’
Scattering/diffraction patterns collected on
DUBBLE
• diffractiepatronen
Multidisciplinary applications
hip replacements
Unwashed Eskimo hair
polymer fibers
tubulin, cell division
Etc., etc., etc….
nano technology
Car exhaust
Soot of diesel
researcher (no safety glasses…)
SAXS
detector
sample
WAXS
detector
National Geographic Magazine
Human skin
Epidermis
(150 μm)
Dermis
(2000 μm)
Subcutaneous
fat
Joke Bouwstra
Division of Drug Delivery Technology
Leiden/Amsterdam Center for Drug Research (LACDR)
Outer layer: Stratum Corneum
‘designed’ as barrier for externl influences
Lipiden (fat)
matrix
Transdermal drug delivery
Penetration
route
corneocyte
Hoorn
laag
Stratum granulosum
Stratum spinosum
Stratum basale
Dermis
Epidermis
Blood vessels
Lateral order of SC lipids
~0.46 nm
0.41 nm
0.41 nm 0.37 nm
d
liquid
More rigid
hexagonal
penetration more difficult
orthorhombic
SR required
- In 5 seconds a pattern
- Weak peaks not visible with
conventional rotating anode
Since we have plenty of X-rays:
• We can measure fast
• Phase diagram of lipids can
be determined
• The effect of pharmacutcals
can be studied on-line
• Relatively small amounts of
material required (important
in patient derived samples)
In fact three (related) research areas:
1. Development of biofilms based upon vernix
caseosa.
2. Studying lipid structure of diseased skin
3. Development of lipid substitutes for skin
penetration studies (saves some test animals)
‘high five rabbits’
Patent granted
In our first experiments in Daresbury, about 20 years
ago, we used about 50 neatly stacked strips of skin.
Nowadays we only have to use a single one. I can
estimate that we require 100 x less material.
Prof. Joke Bouwstra
Since 1990:
> 60 publications with SR
10 cited ≈ 100 or more
X-ray spectroscopy
X-ray spectroscopy
‘electron orbits’
deformed
‘electron orbits’
Metal atom
Metal atom
‘neighbours’
ionisation
Röntgen photon
absorbed
It
(E)
I0
Difference in surroundings of metal atom;
difference in absorption spectrum
Powder diffraction
Incoming intensity
absorbed intensity
Sample cell
Again multidisciplinary
catalysis
pharmaceuticals
Hydrogen storage
Environmental pollution
Etc., etc., etc….
liquid metals
electro chemistry
cultural heritage
Catalysis: are small particles
always better?
Marcel di Vece, .., P. Lievens PRL 100, 236105, 2008
• Small catalytic particles have a high
surface/volume ratio.
• Reactions take place at the surface.
• Should we always try to make particles
as small as possible?
• Effects of hydrogen.
• Movie unable to incorporate in pdf
• Some atoms get disconnected due to the
hydrogen treatment
• They re-attach predominantly to larger
particles
• The large particles grow at the expense of the
small ones (Ostwald ripening)
• Conclusion: loss of active catalytic surface
Only with EXAFS we can see what happens with the smallest particles
Technique combinations
• Movie unable to incorporate in pdf
How do I make a working catalyst?
Groep Bert Weckhuijsen, Utrecht
Structure grows
1. Early in reaction, no crystal, X-ray
spectroscopy (XAFS)
2. A little later, X-ray diffraction WAXS
3. When it has grown sufficient, SAXS
4. In the end catalytic activity XAFS,
(UvVis, Raman spectroscopy)
All these steps one wants to study on-line
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Infrastructure
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Industrially
relevant
conditions
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High gas
pressure
Flow
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Operando
conditions
In-situ multi-technique approach of zeolite synthesis
1.5
Normalised Absorption
B
1.0
0
20
30
40
0.5
A
66.7
0.0
50
7700
640
660
680
Raman Shift cm
XAFS
Raman
UV-Vis
584
SAXS
625
542
1.0
0 .0 0 1 6
3.3
*
400
I(q).q [a.u]
Absorbance
1.5
470
525
600
Wavelength (nm)
7800
Energy (eV)
-1
800
0 .0 0 0 8
0 .0 0 0 0
0 .0 1
0 .1
lo g (q ) Å
-1
WAXS
7900
Unique instrumentation
• Sample at high pressure/temperature
• Simultaneous 5 techniques possible
• All aspects of the sample and kinetics
can be studied simultaneously
We can:
• Follow particle growth
• Study the catalytic actions
• Follow the life cycle of the
catalyst
Catalyst crystals
All in a single experiment !
Technique combinations and
sample control
• Already for 20 (10) years a speciality of
the NWO (DUBBLE) beam lines
• Studies of physical-chemistry processes
on-line
Another SAXS example
From picture to ‘icon’
Yousuf Karsh
Picture
Icon
Required:
• Good picture
• Good quality reproduction
• Large scale/volume reproduction
H. Terryn, T Rayment and coworkers
Offset rotation printing
Dampening roller
Ink roller
“Offset” Blanket
Ink film
Paper
Plate cylinder
with printing
plate Oleophilic image area
Hydrophilic non-image area
Impression cylinder
This lithographic method is being used for high quality printing
750 x 106 m2/jaar
The Aluminium surface
• Is being prepared with electrochemistry
• Controlled roughness required (uniform pitting)
surface
Aluminium hydroxide layer
AC current
High Voltage
High Amperage
Small pit blocked
During electrolysis:
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Roughness changes
Layer of ‘smut’ forms
Composition unclear
So far only studied with off-line
techniques
• SEM, XPS etc. (vacuum
required)
With on-line SAXS experiments:
• Electrolysis creates gas
bubbles
• This influences the
transport properties of
‘smut’
∞
Q = ∫ q 2 I (q )dq = (Δρ ) 2 ϕ smutϕ gas
0
• SAXS gives unique
possibilities to study this
process on-line
• Fundamental knowledge of electrochemical
problems
• But applications very close
The perfect garbage bag
Groepen:
P. Lemstra
H.E.H. Meijer
polyethylene
Molten it looks like spaghetti
SAXS
In solid state semi-crystalline
- amorphous parts
- crystalline parts
The ratio amorphous/crystalline and the
spatial orientation determine the
macroscopic properties
WAXS
Polymer processing
With a little pre treatment crystallisation is easier
Orient the polymer chains first
Chains can be oriented by pulling,
Pushing, shearing etc
After that crystallisation is much easier
Why polyethylene?
• Invented already in 1933
• 80 million metric tons/year
• It used to be low quality materials
Better materials
• Through better catalysis, better materials
• Controlled polymer chain lengths
• Mixtures of bimodal chain lengths have
unique properties
• Recycling no problem
• Fundamental knowledge of the crystallisationprocess of blends has to be improved
Film blowing
• Way to make films
•Movie unable to incorporate in pdf
• Molten polymer
• Annular die
• Extrusion
SAXS
WAXS
X-ray beam
Scattering pattern
elongation multiaxial
Each year:
• We use enough of
this to cover the
earth 3x
• A reduction in
thickness whilst
retaining strength….
• Less oil required
• Less polution
• Etc.
But even a garbage bag becomes a piece of ‘high tech’
The future of EXAFS
• A conventional beam line 40 – 80 meter
• In Japan there is a line of 1 kilometre
• We want one of several light years
X-ray stars and interstellar dust
• In super novas iron rich dust is created
• In super novas dust is also being
destroyed
• There is a surplus of dust in the universe
• Where does this come from and is it all
the same composition?
• The spectra of different classes of X-ray
stars are well known
• Measure on earth the spectrum
• The differences between the well known
source and the measured data make it
possible to reconstruct the EXAFS
pattern, i.e. the mineral structure
Use the Milky Way as radiation source
- X-ray spectrum of stars known
- On earth we can see what is absorbed
The role of DUBBLE:
• The dust is iron rich
• Pure, amorphous or crystalline iron
silicates
• Calculate the EXAFS spectrum as
function of position in Milky Way
• Different position, different dust???
• Very accurate EXAFS calibration spectra
required
DUBBLE
We hope no weird
results will be found
500
400
totaal aantal
publicaties
June 2010
300
200
100
0
1996
500e
1998
2000
2002
2004
jaar
2006
2008
2010
Group Lekkerkerker
University Utrecht
Ex VUB
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Largest Dutch-Flemish collaboration
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> 80 publications/year in many different fields
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500-600 visiting
researchers
technicians
students
per year
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7 DUBBLE staff and several ESRF colleagues
enable this
DUBBLE (and ESRF) research:
• Ranging from very fundamental to
very applied
• Ranging from life sciences to hard
core physics
• A real toolbox for Dutch
researchers
Thanks for your attention