Ivan Yordanov highlights

Content
2
Aims
State of the art
Pt and Cu clusters in nanosized BEA zeolite: γ-irradiation and thermal
reduction
Pt clusters in BEA zeolite: plasma treatment
Preparation of Cu doped nanosized LTA zeolite – in situ incorporation
Conclusions

3
Aims
I. Synthesis of nanosized porous materials
- BEA & LTA types zeolite frameworks - crystal size - 10-500 nm
II. Preparation of metal (Me) contain molecular sieves
- Via two step approach: ion exchange follow by
= γ-irradiation
= plasma treatment
= thermal reduction
- Via one step approach using metal contains template
III. Preparation of metal doped thin porous films
IV. Me clusters in porous host for sensor application

4
State of the art: molecular sieves
Molecular sieves are porous solids contain channels system
run through the entire particle, interconnecting the cavities and
terminating at the particle surface.
Zeolite membrane for gas separation

5
State of the art: zeolites
Zeolites are crystalline microporous aluminosilicates with a three-dimensional
framework structure that forms regular channel system with molecular
dimensions running throughout the zeolite crystals.
The zeolite framework is consisting from corner sharing SiO4 and
AlO4 tetrahedra
Extraframework counter cations which are under-coordinated by
the framework
Zeolite A type LTA structure Zeolite Beta type BEA structure

6
State of the art: approaches for metal doping
Building nanomaterials
1. Top-Down
Για να καταλάβουμε τα πολλά και τα μεγάλα πρέπει να κατανοήσουμε πρώτα τα μικρά
To understand the very large, we must understand the very small
Δημόκριτος-Democritus
2. Bottom-Up
The glass appears green in daylight (reflected light), but red when
light is transmitted from the inside of the vessel.

7
Cluster size and location in porous frameworks
Small clusters containing below 4 nuclearity located in the small cage or side
pockets of the zeolites
Low nuclearity metal cluster ( < 40 nuclearity) – situated in the zeolite cages
or in the intersection spaces
Metal clusters with more than 40 nuclearity, located in the channels or on the
particle surface
Examples: Pt and Ir in
sodalite cage in Faujasites
Super-cage in Faujasites
BEA zeolites
Pt clusters in LTL

8
Approaches for preparation of Me doped …
Reducing agents
chemical reduction / γ-irradiation
Impregnation of zeolite frameworks
Adsorption and decomposition of zerovalent metal compounds

9
Approaches for preparation of Me doped …
Reducing agents
chemical reduction / γ-irradiation
Preparation of metal clusters in ion-exchanged zeolites
In-situ incorporation of metals in zeolite matrixes
(CH3)4N+ & [Cu(EDTA)]2-
into LTA framework
Initial colloidal suspension
Hydrothermal
synthesis

11
Pt clusters in Beta zeolite: BEA zeolite framework…
BEA type zeolite structure
Aperture of the straight channels 6.6 x 7.1 Å – directions [100] and [010]
Tortuous channel with aperture of 5.6 x 5.6 Å –in direction [001]

12
Synthesis of nanosized BEA type crystals
Initial precursor suspension: 7.5 (TEA)2O*: 1 Al2O3
**: 25S iO2
***: 375 H2O
Aged and hydrothermally treated: 3 days at RT followed by 72 h at 373 K
Purified and ion-exchanged: BEA zeolite crystals have Si/Al= 14 and 0.75 wt.% Pt2+
(TEA)2O* - tetraethyammonium hydroxide, Al2O3
**- aluminum tri- sec-butoxide and SiO2**- fumed silica
10 20 30 40 50
BEA-Pt[(NH3
)4
]
2+
BEA-pure
BEA-C-ICSD-416768
BEA-B-ICSD-160441
BEA-B-ICSD-153254
Intensity[a.u.]
2[deg], CuK
BEA-A-ICSD-153253
10 20 30 40 50
BEA-pure-100 nm
BEA-pure-10 nm
Intensity[a.u.]
2 [deg], CuK
Sample FWHM[21.45°2θ, (013)], [rad] L, [nm] FWHM[22.47°2θ, (031)], [rad] L, [nm]
BEA-pure-10 0.01375 10.7 0.01186 12.5
BEA-pure-100 0.01476 10 0.00623 23.6
Powder X-Ray Diffraction Pattern recorded in Debye-Scherrer Geometry
I. Yordanov, R. Knoerr, V. De Waele, P. Bazin, S. Thomas, M. Rivallan, L. Lakiss, T. Metzger; S. Mintova, Elucidation on Pt Clusters in the Micropores of ZeoliteNanoparticles Assembledin ThinFilms, J. Phys. Chem. C 2010, 114, (49), 20974-20982,

13
PSD and stability of BEA colloidal suspensions
10 100 1000
BEA-Pt-1000
BEA-Pt-300
Colloidal suspension of BEA-Pt
2+
Washed BEA crystal stabilized in water
ScatteringIntensity[a.u.]
Particle size d, [nm]
As prepared suspension of BEA
Dynamic Light Scattering
Particle size distribution
-150 -100 -50 0 50 100 150
BEA-Pt-1000
BEA-Pt-300
Colloidal suspension of BEA-Pt
2+
Washed BEA crystals stabilized in water
Intensity[a.u.]
-potential [mV]
As prepared suspension of BEA
Stability of zeolite suspensions
ζ – potentiel values
Hydrodynamic diameter: 25 – 50 nm ζ - potential value: from -50 to -35 mV
No change of the PSD and ζ-potentiels during post–synthesis treatments

14
Preparation of Pt clusters via γ-radiolysis
Pt plasmon band at 240-
260 nm due to formed Ptn
0
clusters
UV-vis spectra of Pt-clusters
n
mm
aq
aq
aq
h
MMnM
MMe
MMM
MMe
OHOHHOHeOH




 




2
0
)1(
2
0
0
22
**
32

200 300 400 500 600 700 800
0.0
0.5
1.0
1.5
2.0
300 400 500
0
1
0 5 10
gfedc
b
Dose [kGy]Wavelength [nm]
Absorbence[/cm]
Wavelength [nm]
a
d
c
b
260
249
Absorbence[/cm]

15
Pt clusters in BEA zeolite: HRTEM study
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0
20
40
60
80
100
120
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0
20
40
60
80
100
120
Al
Si
Cu
Pt
Pt Pt
Intensity[Counts]
Energy [keV]
BEA-Pt-300
Al
Si
Cu
Pt
Pt
Intensity[Counts]
Energy [keV]
Pt
BEA-Pt-1000
Scale bar = 10 nm
Average diameter of BEA zeolite crystals: 10 nm
No Pt cluster outside of the BEA crystals
Pt clusters are situated in the BEA channels
Size of Pt clusters: 1-2 nm
dPt(220) =0.23 nm
dBEA(100) =1.26 nm
I. Yordanov, R. Knoerr, V. De Waele, P. Bazin, S. Thomas, M. Rivallan, L. Lakiss, T. Metzger, S. Mintova, Elucidation on Pt Clusters in the Micropores of ZeoliteNanoparticles Assembledin ThinFilms, J. Phys. Chem. C 2010, 114, (49), 20974-20982,

1717
1. Coating suspension:
-1 wt. % zeolite suspension
-co-solvant: ethanol
-binder: 0.7 wt.% methyl cellulose
2. Spin coating deposition:
3. Conditions of spin coating:
1st layer 60 s at 4000 rpm
2nd – 4th layers 30 s at 1600 rpm and
5th – 6th layers 60 s at 3600 rpm
All films contain 6 layers
500 nm
500 nm
500 nm
Preparation of zeolite films

18
Grazing-Incidence X-Ray Diffraction
0.0 0.1 0.2 0.3 0.4 0.5 0.6
1
10
100
1000
Incident angle 
, [deg]
Penetrationdepth,[Angstrom]
Principal scheme: GI-XRD geometry
Characterization of films at different penetration depths Λ = f (Q)
500 nm
'
i
''
i
'
f
''
f
  1
Im

 ZQ

19
Pt-clusters in BEA films: GI-XRD patterns
BEA-Pt film: 1000 Gy
27 37 47 57 67 77
i
=0.1°
i
=0.05°
Intensity[a.u.]
2 [deg]
Pt(111)
Pt(200) Pt(220)
5 6 7 8 9
Intensity[a.u.]
2 [deg]
27 37 47 57 67 77
Pt(220)Pt(200)
Pt(111)
i
=0.1°
i
=0.05°
Intensity[a.u.]
2 [deg]
Pt-BEA films: 300 Gy
Small clusters Big clusters
Scherrer’s equation:


cos.
.
FWHM
K
L
Average cluster size: 1-2 nm

20
Ellipsometry investigations
200 300 400 500 600 700 800 900
1.2
1.3
1.4
1.5
1.6
1.7
1.8
Indexofrefraction
Wavelength [nm]
Principal scheme: Ellipsometry
Film thickness: 200 - 500 nm
Increase of the density of the materials leads to
higher values of index refractive index
200 300 400 500 600 700 800 900
0
10
20
30
40
50
60
70
80
90
75°
,[deg]
Wavelength , [nm]
65°
Cauchy modelling
Optical properties
Beta
Pt-Beta-300
Pt-Beta-1000

21
Preparation of Pt clusters in BEA zeolite by cold plasma3750
3500
3250
3000
2750
2500
, [cm
-1
]
t,[sec]
25
0
A
BEA-Pt-2+ in O2
Before plasma treatment
After plasma treatment
3750
3500
3250
3000
2750
2500
AHC
25
t,[sec]
0
A
, [cm
-1
]
In Situ FTIR study of TEA decomposition from BEA zeolite
M. Rivallan, I. Yordanov, S. Thomas, S. Mintova, F. Thibault-Starzyk, Plasma Synthesis of highlydispersed metal clusters confained in nanosized zeolites. ChemCatChem 2010, 2, (9), 1074-1078
BEA-Pt-2+ in N2
The CH3- stretching modes at 3100 - 2800 cm-1
originating from the TEA+ -ion vanishes due to
plasma decomposition of TEA+ -ion.

22
Pt clusters in BEA zeolite for CO sensing
10 20 30 40 50
BEA pure
BEA-Pt
2+
Intensity[a.u.]
2deg], CuK
BEA-Pt
Pt
Stability of Pt clusters and Beta host
2150 2125 2100 2075 2050 2025
, [cm
-1
]
0,02 a.u.
A
CO chemisorbed on Pt-BEA BEA-Pt sample treated in
O2 plasma
The band at 2086 cm-1 of Pt-CO increases with
the concentration of CO
Global process: from template removal to formation of Pt0
M. Rivallan, I. Yordanov, S. Thomas, S. Mintova, F. Thibault-Starzyk, Plasma Synthesis of highlydispersed metal clusters confained in nanosized zeolites. ChemCatChem 2010, 2, (9), 1074-1078,
Bragg’s reflections at 39.8° and 46.3 ° 2θ from
Pt0 with hkl – values (111) and (002)

23
Copper clusters in BEA zeolite
10 20 30 40 50
Intensity[a.u.]
2 [deg], Cu K
BEA pure
BEA-Cu
2+
Crystallinity of the sample
10 100 1000
ScateringIntensity[a.u.]
Particle size d, [nm]
BEA pure
BEA-Cu
2+
Particle size distribution
(TEA)2O* - tetraethyammonium hydroxide, Al2O3 ** -aluminum tri- sec-butoxide and SiO2 **- fumed silica
BEA-Cu2+ BEA-Cu-species
Thermal treatment at 723 K for 6 h
Initial precursor suspension: 7(TEA)2O*:1.9Al2O3
**:100SiO2
***: 1000H2O
Aged and hydrothermally treated: 27 h at RT followed by 72 h at 373 K
Purified and ion-exchanged: BEA zeolite crystals have Si/Al= 14 and 1.74 wt.% Cu2+

24
i r
21002125
2150
2175
2200
Ar
Ar
Ar + CO
Tim
e
Wavenumber [cm
-1
]
0.2 a.u.
C
u
+-C
O
-2157
cm
-1
C
u+
-(C
O
)
2-2177
cm-1
500 nm
CO chemisorbed on Cu species
Cu-doped zeolite Beta
nanoparticles have good sensing
response to CO.
The solid films Cu-BEA/QCM can
be used for sensing applications.
Thin film on QCM
Spin coating deposition
Coating suspension
Thin film on QCM from
zeolite Beta nanocrystals
doped with Cu species
Operando DRIFTS study
Gas composition:
Lean flow: Ar
Rich flow: 4000 ppm CO
Total flow = 10 ml.min-1
Gas vector: Ar
IR bands:
2157 cm-1 - Cu+ - CO
2177 cm-1 - Cu+(CO)2
Cu doped zeolite film on QCM for gas sensing

26
Structure of zeolite Linde A
β – cage
(sodalite cage) - [4866]
α – cage - [4126886]
The cages of zeolite A can host different cations such as Na+, K+,
Ca+, Cs+, NH4
+ etc.
LTA zeolite framework has 3D pore structure with pores running
perpendicular each other in x, y and z planes
4.2 ÅD4R
O
Na+
Na+
O

27
Synthesis of zeolite A crystals
Sample name Molar ratio Template T,°C t,h dH,nm
tf-Na-LTA 2.5Na2O*:1.5Al2O3
***:2SiO2
***:110H2O template free 60 24 410
Na-TMA-LTA 13.5(TMA)2O:1.8Al2O3
**:11.3SiO2
**:0.29Na2O*:763H2O [(CH3)4N]+ 70 24 170
Cu-EDTA-TMA-LTA 13.4(TMA)2O:1.7Al2O3:11.2SiO2:0.25[Cu(EDTA)2]2-:5NH3:650H2O [(CH3)4N]+
2[Cu(EDTA)]2- 70 72 280
Chemical composition of the initial systems and conditions of synthesis
LTA zeolite crystals have been separated from the mother liquid by double centrifugation at 13 000 rpm for 15
mins. After each cycle the zeolite crystals were re-dispersed in Milli-Q water using the ultrasonic bath for 1h in ice.
Na2O* - NaOH, (TMA)2O - tetramethylammonium hydroxide, Al2O3
**- Al(O-i-Pr)3, Al2O3
*** - sodium aluminate, SiO2
** - LUDOX SM-30 SiO2
*** - sodium silicate
[(CH3)4N]+-ion
~6.4 Å
[Cu(EDTA)]2—complex
~7.8 Å
β – cage
(sodalite cage)
Cage inner space ~6.5 Å
α – cage
Cage inner space ~11.4 Å

28
PXRD data
Powder X-Ray Diffraction Pattern recorded in Bragg-Brentano Geometry
Experimental XRD patterns contain all typical for LTA framework Bragg’s reflections at:
2θ = 7.2 ° => (200); 2θ = 10.2 ° => (220); 2θ = 12.5 ° => (222); 2θ = 24.2 ° => (622)
Cu2O Bragg’s reflections at:
2θ = 36.5 ° => (111) and 2θ = 42.4 ° => (002) - have not been observed
5 10 15 20 25 30 35 40 45 50
29.152
Intensity/a.u.
2deg, Cu K
Simulated PXRD pattern
tf-Na-LTA
Na-TMA-LTA
Cu-EDTA-TMA-LTA
17.202
200
220
222
622
I. Yordanov, I. Karatchevtseva, H. Chevreau, M. Avdeev, R. Holmes, G. Thorogood, T. Hanley, One-step approach for synthesisof nanosized Cu-doped zeoliteA crystalsusing the Cu-EDTA-complex. Micropor. Mesopor. Mat. 2014, 199, pp 18–28

29
In situ PXRD & TG-DTA data sets
10 20 30 40 50 60 70 80
29.152
Temperature/°C
Intensity/a.u.
2deg, Cu K
17.202
35
100
125
150
175
200
250
300
450
35
15 20 25 30 35
Temperature/°C
Intensity/a.u. 2deg, Cu K
35
100
125
150
175
200
250
300
450
35
25
20
15
10
5
0500
400
300
200
100
0
24.46
24.48
24.50
24.52
24.54
24.56
24.58
24.60
450
250175
Temperature / °C
CellParametera/‫إ‬
Time / hours
24.47649
35
24.60318
125
24.60032
24.60420
24.53904
24.53703
35
cooleddown
Temperature-dependent in situ XRD data sets
Cell parameter a estimated from X-ray data
sets, as a function of temperature
Zeolite cell parameter a :
- in the range 35 -125 °C increases due to a thermal
expansion of both zeolite framework and occluded
organic template
- in the range 125 -250 °C is nearly constant
- at 175 ° C contracts due to a release of H2O from the
framework.
- in the range 250- 450 °C decreases due to removal of
H2O and thermal decomposition of various organic
species.
- at 35 ° C (cooled down) is higher in comparison to the
initial value due to trapped carbonaceous char.
Low-intensity and very
broad Bragg reflections
were observed between
17.20 ° and 29.15 ° 2θ.
The intensity of the
additional reflections in all
patterns between 35 ° C
and 175 ° C decreases with
increasing the temperature.

3030
TG-DTA data
Cell parameter a estimated from X-ray data
sets, as a function of temperature
100 200 300 400 500 600 700 800 900 1000
60
70
80
90
100
Weightchange/%
Tempareture / °C
-20
0
20
40
60
80
100
DTA/V
-2.0
-1.5
-1.0
-0.5
0.0
DerivativeWeight/%.(°C)
-1
Endo
Exo
C)
TG-DTA data
< 100 °C - releasing of unbound or free H2O
175 - enlarged pore apertures allow H2O molecules to
escape from the cages.
100 - 200 °C - releasing of chemically bound H2O
250 - 420 °C - the thermal decomposition of
[Cu(EDTA)]2- -ion
450 -500 °C - thermal decomposition of TMA+ -ion.
>500 ° C - slow ongoing mass-loss.
35 - 250 ° C - thermal expansion of both
zeolite framework and template
175 ° C - contraction of the a due to a
release of H2O from framework
250- 450 °C - a decreases due to removal of
H2O and thermal decomposition of various
organic species.
25
20
15
10
5
0500
400
300
200
100
0
24.46
24.48
24.50
24.52
24.54
24.56
24.58
24.60
450
250175
Temperature / °C
CellParametera/‫إ‬
Time / hours
24.47649
35
24.60318
125
24.60032
24.60420
24.53904
24.53703
35
cooleddown

31
SEM - EDX data
200 nm
0 2 4 6 8 10
0
1000
2000
3000
4000
5000
6000
7000
8000
Na K
Cu, K
C K
O K
Na K
Cu, K
Intensity/Counts
Energy / keV
Si K
Al K
Cu, K
Si K
Al K
0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
0
1000
2000
3000
4000
5000
6000
7000
8000
Intensity/Counts
Energy / keV
Energy-dispersive X-ray spectrum
Energy-dispersive X-ray analysis
confirmed the presence of Cu2+-ion in the
Cu-EDTA-TMA-LTA zeolite nano-crystals
with the Cu peaks evident at 8.1 keV (Kα1)
and 0.93 keV (Kβ1)
SEM secondary micrograph
Cu-EDTA-TMA-LTA zeolite nano-crystals are
predominantly spherical in shape with the
crystal size in the region 170-280 nm.

32
ESR spectrum
The asymmetric ESR spectrum suggests that the ligands (the O-atoms from COO--groups)
along the z axis are much more screened from the Cu2+ ion than are the four radial
ligands (2 N- and 2 O-atoms from chelate ring) along the x and y axes.
2500 3000 3500 4000
500 Gauss
X-band magnetic field strength / Gauss
T
g = 2.08
gII
= 2.30
AII
= 150
Cu2+ ion - (d9 – t6
2ge1
g)
O
N
Cu[EDTA]2- -complex LTA zeolite framework

33
FTIR spectra
The IR spectroscopy clearly shows the presence of bands due to bonding of copper to nitrogen and oxygen atoms
from the EDTA4--ion, which is an indication of existence of a [Cu(EDTA)]2--complex in the LTA zeolite framework.
Cu2+ ion
O
N
Cu[EDTA]2- -complex
IR bands:
1635 cm-1 – COO- ··· Cu2+
1618 cm-1 – COO- ··· Cu2+
1109 cm-1 – C–N··· Cu2+
1800 1700 1600 1500 1400 1300 1200 1100 1000 900 800 700
3500 3000 2500
1109
1295
1340
1415
1485
690
838
1350
1385
1618
Wavenumber / cm-1
tf-Na-LTA
Na-TMA-LTA
Cu-EDTA-TMA-LTA
1635
Wavenumber / cm-1
νas-COO-···Cu2+
-νas–CH3
-νs–CH3
(CH3)4N+
-νs-COO-
-ν–C–O
-scis.vib.-COO-
-wag.vib.-COO-
-wag.vib.–CH2
-twist.–CH2
-stretch.–C–N···Cu2+
CH2

34
Raman spectra
1600 1400 1200 1000 800 600 400 200
630
670
1050
1270
1465
1453
1675
1415
490
458
Na-TMA-LTA
Raman shift / cm
-1
tf-Na-LTA
Cu-EDTA-TMA-LTA
1018
Cu2+ ion
O
N
Cu[EDTA]2- -complex
Raman bands:
1018 cm-1 – C – C
458 cm-1 – Cu – N
630 cm-1 – Cu – O
-stretch.–C–C
-C–N–deform.+Cu–N–s.stretch
-νas-COO-
-νas–CH3
-scis.vib.–CH2
-twist.–CH2
-νas–C–N
-νs–C–N
-stretch.–Cu–O
-D4R
I458/I490>1
I458/I490<1
The Raman spectroscopy data is in a good agreement with the IR results confirming the inclusion of the
[Cu(EDTA)]2- -complex in the zeolite framework.

35
20 40 60 80 100 120 140 20 40 60 80 100 120 140
20 40 60 80 100 120 140 0 100 200 300 400 500
24.46
24.48
24.50
24.52
24.54
24.56
24.58
24.60
24.62
Intensity
2 / (°)
1000 a.u. 200C 500C
Intensity
2 / (°)
1000 a.u.
after cooling to 27C
Intensity
2 / (°)
1000 a.u.
X-ray data set
CellParametera/Å
Temperature / °C
Neutrons data set
Non-ambient Neutron Powder Diffraction study
LeBail analysis on neutron data sets recorded in Debye-Scherrer Geometry
Both the in situ XRD and NPD techniques show good agreement demonstrating the expansion
of the zeolite cell during thermal treatment followed by subsequent contraction with the
decomposition of the organic template.
ECHIDNA
High-Resolution Powder
Diffractometer

36
Conclusions
Nanosized zeolite crystals (with BEA type framework  10 nm & LTA framework
< 300 nm) have been synthesized by hydrothermal treatment using
conventional heating.
Formation of metal clusters (Pt & Cu) can be achieved by different reducing
approaches : i) γ-radiation, ii) plasma treatment, iii) thermal treatment.
The selective detection of CO on Pt- and Cu- containing porous films is
demonstrated.
Cu doped nanocrystals of zeolite A have been prepared by one step approach
of incorporation of Cu-EDTA complex into LTA framework during the zeolite
synthesis
The metal containing nanomaterials assembled in thin films are of great
importance for gas chemical sensing application mainly for selective detection
of CO, CO2 and hydrocarbons.






37
Dr Svetlana Mintova – thesis supervisor
Dr Till Metzger – beam scientist ID01 at ESRF
Dr Gèrald Chaplais – MOF synthesis
Dr Vincent de WAELE -– γ-irradaition
Dr Mickaël Rivallan – FTIR spectroscopy
Dr Sébastien Thomas – mathematical modeling
Dr Inna Karatchevtseva – Raman spectroscopy
Dr Hubert Chevreau – LeBail on X-ray data sets
Dr Maxim Avdeev - beam scientist ECHIDNA beamline at ANSTO

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