Advanced Characterization of Materials: Relevance and Challenges.
1. Advanced Characterization of Materials
Relevance and Challenges
Aldo Craievich
Instituto de FĂsica
Universidade de SĂŁo Paulo
SĂŁo Paulo âSP
craievich@if.usp.br
XV Meeting of the Brazilian MRS,
Campinas, 5 to 9 September 2016
Institute of Physics
University of Sao Paulo
2. Advanced Characterization of Materials.
Relevance and Challenges
Outline
I - Structural characterization of materials and Crystallography. Relevance.
II - A short historical view of Crystallography, X-ray diffraction and diffuse scattering.
III - The use of synchrotron radiation sources. First Brazilian second-generation synchrotron
IV - New advanced techniques. Fourth-generation synchrotrons.
V - New advanced techniques. Fifth generation light sources (X-ray free electron lasers).
VI - New advanced facilities for investigations of materials in Brazil.
VII - Challenges, future trend and final remarks.
3. I - Structural characterization of materials
and Crystallography.
Relevance
4. Crystallography. Structure and properties of materials
Purpose
Understanding the properties of materials and mechanisms of transformation
based on experimental measurements by using X-ray scattering techniques
and theoretical foundations:
- Determinations of atomic and electronic structures at different length and
time scales,
- Applications of theories associated to material properties (based on quantum
mechanics, dislocation theory, statistical mechanics, thermodynamicsâŠ).
Consequence
Helping developments of new materials with desired properties
5. Chemical and physical
properties
Theory of solid-state
physics and chemistry
Atomic and electronic
structures at different spatial
and time resolution
Understanding the properties of materials
7. An example of structural characterization ad understanding of a physical property
Semiconductor quantum dots embedded in a transparent glass
Optical properties
A
A
Doped-glass
melting
Quenching
Isothermal growth of
semiconductor NPs
S1
S2
S3 S1 S2 S3
Temperature
Time
Room
temperature
Visible
(white) light
8. Example of structural characterization ad understanding of a physical property
Semiconductor quantum dots embedded in a transparent glass
A
A
Egap
Structural transformation
(Time dependent structure)
From basic theory:
Efros and Efros equation
Egap=(Egap)macro - K/R2 Property Nanostructure Electronic structure
9. Classical X-ray diffraction and materials structure
âȘ The most frequently used experimental procedure for studying the structure of materials
is X-ray diffraction. Analyses of single-crystal X-ray diffraction patterns reveal the
geometry of unit cells and the coordinates of the atoms inside them.
âȘ The problem is that atomic structures of unit cells determined by applying this technique
are time averages and spatial averages of many instantaneous and local structures,
respectively.
âȘ For this reason, the results derived from classical single-crystal X-ray diffraction patterns
do not describe neither instantaneous configurations of moving atoms nor detailed local
structures of point, linear, surface and volume defects.
âȘ This restrains our understanding of the properties of materials that depend more on their
instantaneous structure or local configurations of structural defects than on the features
of their time or spatially averaged structures.
âȘ However extremely important discoveries were achieved during the 100 years lasted from
the first use of X-ray diffraction associated to the scientific field of Crystallography, which
led to more than 40 Nobel prizes in Physics, Chemistry and Medicine.
10. II - A short historical view of 100 years
of Crystallography, X-ray diffraction
and diffuse scattering
11. 1914 â First unit cell structure determinations-
Bragg (father and son)
1939 â Hardenning of aluminum-copper alloys .
Guinier-Preston zones
~1950 â Structure of proteins. Perutz and Kendrew
1952 â Structure of DNA. Watson and Crick
1984 â Quasi-crystals â Schectmann
2005 â Graphene - Geim and Novoselov
One hundred years of Crystallography:
X-ray diffraction and materials structure
1912 â First X-ray diffraction pattern - Laue
1914 â Coolidge X-ray tube
1980 â Dedicated synchrotron sources
2009 â X-ray lasers
2016 â 4th generation synchrotron sources
12. First structure determined by X-ray diffraction.
Sodium chloride (NaCl)
FCC cubic Bravais
lattice
Na+ at (0,0,0)
Cl- at (œ,0,0)
W.L. Bragg, W.H. Bragg (1913) 2dsin q=l
14. X-ray diffraction pattern of DNA
Structure model derived from XRD patterns
James Watson
and Francis Crick (1953)
15. X-ray diffraction pattern of DNA Structure model derived from XRD patterns
L=34,0 A
d=3,1 A
2Ï/d
2Ï/L
Analysis of XRD patterns and determination of relevant
structural parameters
16. I - Formation and growth of Guinier-Preston zones in
AlCu alloys (One of the first nanostructured materials
developed by a bottom-up procedure).
First successful study of a nanostructured material:
Aged Cu-doped Al alloys
(A. Guinier, Nature 1938)
17. Aluminum alloys
Wilm (Germany) discovered in 1906
the effect of age-hardening of aluminum alloys.
Al alloy
quenched in
water and aged
at room
temperature
Quenching
Aging at room or at higher T
Solution treatment
Time
α
α
Ξ
Hardness
18. Aluminium 99,985%.
Aluminium and aged aluminum alloy
1920: Merica (EEUU)
suggested that age-
hardening is related to the
presence of submicroscopic
precipitates, without any
experimental evidence for
this statement.
Aluminium-4%copper
Time
Quenching
Aging
Solid solution
Al Composition (w.% Cu)
1906: Wilm (Germany)
discovered the effect of age-
hardening of aluminum
alloys in 1906
19. Diffraction
pattern of pure Al
Diffraction
pattern of aged
Al Cu alloy
X-ray powder diffraction analysis of Al alloys
Why apparently age hardening
of AlCu alloys is not
accompanied by a parallel
structural transformation?
Why aged AlCu alloys harden?
22. III - The use of synchrotron
radiation sources. First Brazilian
second-generation synchrotron
23. The 1.37 GeV UVX Brazilian second generation synchrotron light source in operation at LNLS, Campinas
(1997 â 2018)
Synchrotron X-ray, VUV, Vis and IR light sources based on electron storage rings
1st generation (1960):
Electron storage rings previously built for applications to high energy physics used in âparasiticâ mode.
2nd generation (1980):
Electron storage rings built for using synchrotron light mainly produced by bending magnets.
3rd generation (1990):
Electron storage rings built for using synchrotron light mainly produced by undulators.
UVX electron storage ring
Electron energy: 1.37 GeV
Emittance: 100 nm.rad
25. Mini-Curso âEspectroscopia de Raios Xâ
realizado na sede de Faz. Santa CĂąndida
Os participantes visitam a ĂĄrea onde foi
depois construida a fonte de luz
sĂncrotron do LNLS (1990)
(1991) Starting the excavation of the
tunnel for the 120 MeV injector linac
26. Main Building
First LNLS beam lines
Beam lines and emission spectrum
First visible fluorescence effects
produced by X-ray photons at LNLS (1997)
34. Needing characterizations of
local structures of single nanocrystals
âȘ The decreasing trend and suppression of undercooling in Bi nanocrystals with decreasing
sizes were explained by a simple two-phase model consisting of a crystalline core surrounded
by a disordered shell (Kellermann and Craievich Phys Rev, 2008).
âȘ This conclusion is an indirect evidence of the heterogeneous nature of nanoparticles. In
order to confirm the core-shell model of the local structure of single nanocrystals should be
determined.
âȘ Melting and freezing of central core and âshellâ structure - close to the external surface of
nanocrystals - do not simultaneously occur. Again this heterogeneous melting process
requires a local structural characterization of individual nanoparticles.
Core-shell
model
Melting
Phase diagrams of nanocrystals were determined for samples composed of nanocrystals with a rather
wide size and shape distribution (Abdala et al, PhysChem-ChemPhys, 2010). Structural studies of
individual crystals with different known sizes and shapes would provide a more detailed basic
description of phase diagrams and phase transitions.
35. IV - New advanced techniques.
Fourth generation synchrotrons.
36. MAX IV: First fourth generation synchrotron light source in
operation (21 June 2016) - Lund (Sweden)
âȘ Max IV has a circumference of 528 meters, operates at 3 GeV energy, and has been
optimized for high-brightness X-rays (Electron-beam emittance < 1nm.rad).
âȘ There are also plans for a future expansion of the facility that would add a X-ray free
electron laser (XFEL) to the facility, but is yet to be funded
MAX IV
Electron energy: 3 GeV
Emittance: 0.2 nm.rad
LNLS UVX
Electron energy: 1.37 GeV
Emittance:100 nm.rad
37. âȘ In order to determine the detailed structure, without spatial averaging, the whole
crystal should be considered as an "unit shell".
âȘ This requires the use of an X-ray beam with a volume of coherence larger than the
crystal volume.
âȘ This coherence property allows for the analysis of the total set of relevant
scattering intensities â over all accessible reciprocal space â which, through Fourier
synthesis, leads to the whole material structure (and not the average structure of
the unit cell).
âȘ In other words, the use of coherent X-ray beams is expected to yield "lens-free
imagesâ of instantaneous structures of perfect and imperfect crystals, and even of
amorphous materials.
Determination of local structures by using
fourth generation (very brilliant) X-ray sources
38. âą The experimental setups used for lens-free X-ray imaging (without spatial averaging)
require an incident X-ray beam with large longitudinal and transversal coherence
lengths.
âą The longitudinal coherence length is related to the monochromaticity of the X-ray
beam and the transversal coherence length depends on the size of the photon
source.
âą Fourth generation X-ray sources with very low (diffraction-limited) emittance provide
extremely bright X-ray beams that are expected to satisfy the coherence conditions
for rather large sample volumes.
âą In conclusion, the problems risen by spatial averaging of the structures of inorganic
materials determined by classical X-ray diffraction, are starting to be solved by the
use of very low emittance electron storage rings.
Coherence of X-ray beams emitted by fourth generation
synchrotron sources
45. Resonant Inelastic X-ray Scattering (RIXS)
âș RIXS is an X-ray âphoton in- photon outâ technique, meaning that one irradiates a
sample with X-rays, and observes the scattered X-ray photons.
âą HARD X-RAY
When F. Sette joined the ESRF, his goal was to build a IXS beamline with 1 meV
resolution: the community was very sceptical. Quickly, the energy resolution
achieved reached 1.4 ± 0.1 meV at 21.748 keV. ( ÎE/E = 6 x 10-8). Exciting results
were obtained immediately on glasses and liquids
[1] F. Sette et al, PRL. 75, 850 (1995)
[2] G. Ruocco et al, Nature 379, 521 (1996).
âą SOFT X-RAY: Braicovich, Ghiringelli, Brookes in 2004
Today
E(RX)=10KeV DE=0.1 meV
DE/E= 10-8 !!!
E(RX)=10000 eV
E (phonons) ~kT= 0.025 eV
E(phonons)/E(RX) = 2.5.10-5
46. Progress in RIXS resolution at the Cu L edge (931 eV).
(a) Ichikawa et al. [7], BLBB @ Photon Factory 1996
(b) Duda et al. [8], I511-3 @ MAX II, 2000
(c) Ghiringhelli et al. [9], AXES @ ID08, ESRF 2004
(d) Braicovich et al. [10], AXES @ ID08, ESRF 2009
(e) Braicovich et al. [11], SAXES @ SLS. Breakthrough: 130 meV!
(f) ERIX@ID32, 50 meV, ESRF 2015
(g) ERIX@ID32, 25 meV at the end of the year?
Soon NSLSII, Taiwan, Diamond, SLS...
SOFT X-RAY RIXS
â
RIXS spectra of La2CuO4 at CuL3 edge
47. âąSince 30 years the maximum static pressure generated so far
at room temperature was reported to be about 400 GPa.
âą L. Dubrovisky et al., Nature Comm.
2015 showed that the use of micro-
semi-balls made of nanodiamond
(10-50 ÎŒm) as second-stage anvils
allows to go above 600 GPa
âąOn rhenium and gold they have
studied the equation of state at
pressures up to 640 GPa and
demonstrated the feasibility and
crucial necessity of the in situ
ultra HP measurements for
accurate determination of
properties at extreme conditions.
âąONE NEEDS A VERY SMALL BEAMSIZE TO
MEASURE CORRECTLY THE PRESSURE
X-ray diffraction under extreme conditions (very high pressures)
48. High pressure
L. Dubrovinsky et al., Nature 2015: Powder diffraction of Osmium up to 774 GPa. By compressing Os,
one of most incompresssible metals, to over 770 GPa, they observed a new type of electronic
transition, the core-level crossing (CLC transition), that involves pressure-induced interactions between
core electrons, and leads to observable changes of the material properties. The ability to reach
sufficiently high pressure levels to affect the core electrons of transition metals in static high-
pressure experiments will open up opportunities in the search for new states of matter.
Atmospheric
pressure
DOS
P=392 GPa
Pressure at the
center of earth
49. Some remarks about the real possibilities opened by
the use of coherent X-ray scattering
50. V - New advanced techniques. Fifth generation
light sources (X-ray free electron lasers).
52. âȘ Very bright X-ray sources providing extremely
short photon bunches named X-ray free
electron lasers (XFELs) are currently in
operation in USA (LCLS) and Japan (SACLA)
and under construction in Germany (European
XFEL).
âȘ These new X-ray sources generate very short
(~ a few tenths femtoseconds) photon
bunches. The high power of the photon
bunches rises an apparent problem because
they completely destroy typical samples.
Features of the X-ray FELs
53. âȘ Jet nozzle: 4 micron diameter producing nanocrystals in acqueous
medium (not dry as in electron microscopy nor at cryogenic
temperature as in classical crystallography of nanoscopic samples)
âȘ X-ray photon energy: 1.8 KeV (wavelength: 0.69 nm)
âȘ Pulse duration: 10, 70 and 200 femtosec
âȘ Frequency of X-ray pulse repetition: 30 Hertz (1,800 pulses.sec)
âȘ Detector: 2 pn junction CPDs
âȘ Resolution reaches: 0.85 nm
âȘ Sample dimensions: ~ 200 nm
âȘ Number of X-ray diffraction patterns: 3,000,000
âȘ Number of useful patterns: 15,000
âȘ Spatial group: P63
âȘ a=b= 20.1 nm
âȘ c=16.5 nm
(88 authors !)
54. âȘ Chapmen et al demonstrated experimentally that a single photon-bunch is
sufficient for completely destroy a protein nanocrystal.
âȘ In spite of this, since the photon-electron interaction is extremely fast, diffraction
patterns associated to the initial structure of the nanocrystals (before being
radiation damaged) can be recorded.
âȘ Since in the mentioned investigation a single bunch was not enough for obtaining a
diffraction pattern with good statistical quality, many (~104) protein nanocrystals
were probed.
Serial Protein Crystallography
âȘ The reported results demonstrated
that the use of XFELs solves the old
problem of radiation damage usually
occurring in classical experiments of
X-ray diffraction by protein crystals.
55. XRD pattern in
detector 1 15.103 oriented and merged
XRD patterns, selected from
3.106 recorded patterns
(001) crystallographic plane
Structure determined by
using a free-electron X-ray
laser by applying the
multinanocrystal procedure
(0.85 nm resolution)
Serial crystallography
Structure of a large membrane protein complex (MW: 1MDa)
Structure determined by
classical synchrotron XRD
data taken at 250 K and
truncated at 0.85 nm
resolution
XRD pattern in
detector 2
56. The future of X-ray free electron lasers
The history of and experience with three generations of synchrotron
radiation sources has taught us that the above experiments are at
best the tip of the iceberg of scientific opportunities.
It is safe to predict that we have not yet thought of the most
important experiments that eventually will be done with this new
class of radiation sources â x-ray free electron lasers!
Claudio Pellegrini and Joaquim Sthor
57. âą The principle of Li batteries is based on the reversible insertion and
extraction of Li-ions in the crystal structure of the positive (LiFePO4) and
negative (Li) electrode materials
âą Large volume changes, associated with phase transitions in the
electrode material result in poor cycle performance by mechanical
failure.
Why it is important to study them in real conditions (in situ)?
Because they are used in cell phones, portable computers, âŠ
⊠and also in cars and air planes (This is more serious !)
In situ studies of Li batteries
58. âą Microbeam X-Ray diffraction reveals for the first time the phase transformation in a large number of
(â150) of individual electrodes grains (140 nm). Until now the particle-by-particle model, or mosaic
transformation mechanism predicts the absence of phase coexistence within individual grains.
âą At C/5 (charge in 5 hours), a significant fraction of the (200) LFP and FP reflections during (dis)charge
appear as streaks inferring platelet-shaped domains having an average thickness of 37 nm. In addition,
the average transformation time of individual crystallites is 66 min for the LFP and 37 for FP, in contrast
with one minute predicted if assuming a surface reaction limited process.
Charging voltage
(C/5) including the
evolution of a 2D
(200) LFP and PF
peak (first order
Transition)
Az.
Direct view on the phase evolution in individual LiFePO4 (LFP)
nanoparticles during Li-ion battery cycling.
X. Zhang et al., Nature Communications 23 September 2015. (ID11)
59. Real-time diffraction-topography setup for in situ studies of Si wafers
Rack et al.
Volume 3 | Part 2 | March 2016 | Pages 108â114 | 10.1107/S205225251502271X
White radiation from two undulators
impinges on a silicon wafer.
Both the 220 reflection topograph and
the direct transmission image are
recorded simultaneously.
Both imaging detectors are equipped
with a high-speed camera in order to
allow for a short exposure time (1.28â ”s)
and a high image-acquisition rate
(âŒ35â 500 images per second).
[Rack, A., Scheel, M. and Danilewsky, A.
N. (2016). IUCrJ, 3, 108-114.
60. An (001) Si wafer with Vickers indent
(dotted circles) at the centre. The edges
correspond to the 110 directions.
(a) The 220 diffraction image with all the
cracks, i.e. the final stage, acquired with
1.28 ms exposure time.
(b) The sum of 100 direct images
corresponding to the final stage
Rack et al.
Volume 3 | Part 2 | March 2016 | Pages 108â114 | 10.1107/S205225251502271X
Real-time direct and diffraction X-ray imaging
of irregular silicon wafer breakage
61. Selected images from a series of 3000 showing crack propagation in a
silicon wafer under thermal stress (compare crack c1c in Fig. 2).
(Left) The direct transmission images.
(Right) The diffraction images with the 220 reflection.
Crack propagation
Rack et al.
Volume 3 | Part 2 | March 2016 | Pages 108â114 | 10.1107/S205225251502271X
Ds = 844 m
V = 3.108m/s
T = 844m/3.108 m/s = 2.8 ms
Dt (between bunches) = Dt/4 = 0.7ms
Four bunches
Exposure time: 1.28 ms
Acquisition rate: 35500 frames per sec
Time period between acquisition t = 38 ms
Exposure time: 1.28 ms
62. Propagation of the crack tip as derived from intensity profiles
Rack et al.
Volume 3 | Part 2 | March 2016 | Pages 108â114 | 10.1107/S205225251502271X
Crack tip
position
Time (ms)
Time
Crack tip
position
63. VI - New advanced facilities for
investigations of materials in Brazil
64. Sirius-LNLS: Fourth generation synchrotron source
X-ray diffraction and scattering, absorption and photoelectron spectroscopies
New LNLS synchrotron SIRIUS
Electron energy: 3.0 GeV
Emittance: 0.236 nm.rad
Former LNLS UVX synchrotron
Electron energy: 1.37 GeV
Emittance: 100 nm.rad
65. Fourth generation light sources (synchrotrons)
and
fifth generation light sources (XFELs)
Australian Synchrotron
Canadian
4th generation
light sources
âȘ Lund, Sweden
âȘ Campinas, Brazil
âȘ Grenoble, France
5th generation
light source
âȘ Stanford, USA
âȘ Japan
âȘ Hamburg, Germany
Australian Synchrotron
67. Modern features of materials
structure and properties.
A five dimensional problem
âȘ In order to properly understand the static and dynamic
properties of materials, the structural characterization can
be considered as a vector with 5 components associated to:
3 spatial coordinates (X, Y, Z), time (T), and electron
energy (E).
âȘ All five coordinates (X, Y, Z, T, E) can in principle be
determined by using synchrotrons, neutron facilities and/or
X-ray FELs by applying a number of different techniques:
diffraction, diffuse scattering, absorption, reflectometry,
and electron photoemission.
X
Y
Z E
T
âFive dimensional structureâ
Materials properties
(Time)
(Electron energy)
70. X-ray laserâinduced electron dynamics observed by femtosecond
diffraction from nanocrystals of Buckminsterfullerene
B. Abbey + 21authors
Science Advances 09 Sep 2016:
Vol. 2, no. 9, e1601186
DOI: 10.1126/sciadv.1601186
(A) Summed diffraction data 2500 single shots recorded at
100% power. The semitransparent red circle indicates the
location of one of the reflections only observed in the 100%
XFEL data. (B) Enlarged region from (A) showing Bragg peaks at
10% power, consistent with the room temperature FCC
structure.
Comparing experimental and simulated data.(A) Schematic
representation of the alignment of polarized C60 molecules.
(B) Comparison of the 100% XFEL data and the model
prediction based on the newly predicted, lower symmetry,
structure. The black line shows the difference between the
model and experimental data.
Laser-maximum power
Laser-medium power
Synchrotron
71. Until 1996: Classical X-ray generators for powder and single crystal structural investigations
X-ray diffractometers were available in many Brazilian laboratories from ~1960. SAXS setups were also used
from ~1970 in IFSC, IFUSP and UNICAMP. Recently other laboratories receive new SAXS setups.
1997 â 2018 : LNLS UVX 1.37 GeV electron storage light source, Campinas
In 1997 the first Brazilian synchrotron light source UVX, a second generation 1.37 GeV electron storage ring,
was open to users and is at present in operation at LNLS in Campinas.
2019 - ⊠: LNLS 3 GeV Sirius electron storage light source, Campinas
In ~2019 a fourth generation 3 GeV electron storage ring SIRIUS (now in construction) will be available to users.
2022-⊠(?): A National Neutron Laboratory, associated to the Brazilian Multipurpose Reactor (IPEN) will be
open to users in IperĂł âSP.
This National Laboratory will provide neutron beams with much higher flux than those that are presently
delivered by the beam lines installed at the reactor currently in operation at IPEN.
2025 - ⊠(??) : Brazilian X-ray FEL (?)
The natural following step of LNLS after the first operation of SIRIUS will be to starting the a new project of a X-ray FEL.
X-ray and neutron sources in Brazil
72. âȘ Many novel applications of modern coherent X-ray sources still require
new and challenging developments of very stable optics, in situ
preparation of nanoscopic samples, complex control systems, big-data
analysis procedures and advanced instruments such as fast detectors
with high spatial resolution and high dynamical range.
âȘ Progresses related to these issues are being achieved so as the opening
of the new LNLS synchrotron source (Sirius) to users is expected to bring
new exciting and challenging research opportunities to Brazilian and
international materials science communities.
The future. Challenges
73. Users of the forthcoming fourth
generation synchrotrons and X-ray FELs
are expected to performâŠ
⊠new experiments that apply as much as
possible their singular properties âŠ
⊠avoiding to carry out research works
only involving
âmore of the sameâ!
(Quino cartoon)
Use of the forthcoming 4th and 5th generation X-ray sources
Not to do âmore of the sameâ !
74. Use of the forthcoming 4th and 5th generation X-ray sources
Learn how to use !
⊠if we do not know how to properly use them,
they will never be sufficient!
Independently of how good the ânew toolsâ are and
how many they are âŠ
In order to achieve an efficient use
of the forthcoming fourth and fifth
generation X-ray sources for space
and time resolved structural
characterizations, ...
... we, users, should learn the basic
aspects related to the new
possibilities open by the modern X-
ray sources and understand the
details of the associated
experimental setup.
75. Some personal remembrances
1964 - End of undergraduate studies in physics
at Instituto Balseiro, Bariloche, Argentina
1974 â Participation at the First Meeting of the Brazilian
Crystallographic Association, SĂŁo Carlos - SP
1987 - With Cylon and Ricardo during the first year
of activities at LNLS
2010 - With the new Director surrounded by scientists
celebrating the 20th anniversary of LNLS Users Meeting
76. Acknowledgements
âȘ Yves Petroff, Former Director of ESRF, Grenoble
âȘ Massimo Altarelli, Director of European X-ray FEL, Hamburg
âȘ Ricardo Rodrigues, Sirius Project Director, LNLS
âȘ Harry Westfahl, Scientific Director, LNLS
âȘ Helio Tolentino, LNLS
âȘ Daniel Ugarte, Institute of Physics, UNICAMP
âȘ Hannes Fischer, Jacto/FATEC, Pompeia - SP