Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.
-
date post
24-Jan-2016 -
Category
Documents
-
view
218 -
download
0
Transcript of Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.
![Page 1: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/1.jpg)
Novel Synthesis and Activation Novel Synthesis and Activation strategies leading to the formation strategies leading to the formation
of tuned mesostructuresof tuned mesostructures
![Page 2: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/2.jpg)
Optimal Sorbent and Catalyst Optimal Sorbent and Catalyst support requirementssupport requirements
A. High adsorption capacity High number of active sitesB. High selectivity: * pore volume * pore size distribution * surface area * surface compositionC. Good kinetic properties: selection of * crystal size * particle size * porosity * binder typeD. Good physical properties: * high bulk density * crush strenght * erosion resistanceE. Good lifetime performance: * high chemical, thermal and mechanical stability
![Page 3: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/3.jpg)
Mesoporous Templated SilicasMesoporous Templated Silicas
General IntroductionGeneral Introduction
Mesoporous Templated Silicas (MTS)
MCM- 41MCM- 48
SBA-15SBA-16
PORE DIAMETER
2 - 6 nm 6 - 20 nm
![Page 4: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/4.jpg)
Typical Laboratory Synthesis ConditionsTypical Laboratory Synthesis Conditions
MCM-41
MCM-48
SBA-15
SBA-16
CTMABrGem 16-8-16
Gem 16-12-16
Pluronic P123EO20PO70EO20
Pluronic P127EO106PO70EO106
13
13
<1
<1
TEOS/Fumed silica
TEOS/Fumed silica
TEOS
TEOS
1/ 0.251/0.06
1/ 0.061/ 0.1
1/ 0.02
1/ 0.008
Template pH Silica source
Si/Templ. SynthesisCharacteristics
24 h at RT° + 2 days at 130°C in AC + 3 days HT 5 days at 130°C in AC + 3 days HTstirring 8 h at 45°C + ageing 16 h at 80°C
stirring 8 h at RT° + ageing 16 h at 80°C
Mesoporous Templated SilicasMesoporous Templated Silicas
CTMABr: Cetyltrimethylammonium bromideGemini: [CmH2m+1(CH3)2N-CsH2s-N(CH3)2CnH2n+1]2Br
![Page 5: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/5.jpg)
Structural CharacteristicsStructural Characteristics
Symmetry
Surface Area(m²/g)
Pore Volume(ml/g)
Wall Thickness(nm)
P6m(Hexagonal
)
1000
1.2
1
Ia3d(Cubic)
1200
1.2 – 1.5
1
P6mm(2D Hexagonal)
700-1000
0.7 – 1.3
4 – 6
Im3m(Cubic)
700-900
0.4 – 0.8
5 – 8
MCM-41 MCM-48 SBA-15 SBA-16
Mesoporous Templated SilicasMesoporous Templated Silicas
![Page 6: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/6.jpg)
Pore Size Engineering Pore Size Engineering of MCM materialsof MCM materials
The effect of the synthesis conditions
Influence of the chain length of the surfactant
Addition of co-templates
Tuning pore size distrubution
![Page 7: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/7.jpg)
Pore Size Engineering MCMPore Size Engineering MCM
Synthesis ConditionsSynthesis Conditions
0.5 1 1.5 2 2.5Pore Radius (nm)
dV(r
)
Tuning of the pore size of the MCM material by selecting the synthesis conditions
A
B
C
D
A = 1 day base +1 day HT *r p = 1.0 nm
B = 5 days base + 3 days HTr p = 1.2 nm
C = 10 days base + 1 days HTr p = 1.3 nm
D = 10 days base + 3 days HTr p = 1.5 nm
* HT = Hydrothermal treatment
![Page 8: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/8.jpg)
Pore Size Engineering MCMPore Size Engineering MCM
Influence of the chain length Influence of the chain length
N+ N+
0.5 1 1.5 2Pore Radius (nm)
dV(r
)
Gem 16-12-16
Gem 18-12-18
Physical Properties:
Gem 16-12-16S BET = 1300 m2/gV P = 1.0 ml/gr P = 1.2 nm
Gem 18-12-18S BET = 1600 m2/gV P = 1.4 ml/gr P = 1.3 nm
Synthesis Conditions:5 days at 130°C followed by hydro-thermal treatment of 3 days at 130°C
Difference in surfactant side chain length
![Page 9: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/9.jpg)
Pore Size Engineering MCMPore Size Engineering MCM
Addition of Co –TemplatesAddition of Co –Templates
0
2
4
6
8
10
12
1 1.5 2 2.5 3 3.5 4
Pore Radius (nm)
Dv(
r)
0
0.3 0.6
11.2
1.8
Gemini surfactants
Dimethylalkyl amines
Enlargement of the pore size of MCM-48 due to the addition of dimethyl-hexadecyl amine as a swelling agent with different ratio of amine/surfactant. Other additives can be used like ethanol, decane and different dimethylalkyl amines.
Mechanism:
Micelle
Ratio ofsurfactant
co–template
![Page 10: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/10.jpg)
Morphologies of MCM
Different morphologies: - fibers- layers- gyroids- rods-spheres- ….
![Page 11: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/11.jpg)
Hollow core spheres
Hard spheres
Morphologies of MCM
![Page 12: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/12.jpg)
Cubic core
Hexagonal channels
Morphologies of MCM
![Page 13: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/13.jpg)
Catalytic ActivationCatalytic Activation
OverviewOverview
Methods for catalytic activation
in situ activation (during the synthesis)
post-synthesis modification (after the synthesis)
framework incorporation +
surface modifiction
surface modification
various metal oxides(V, W, Ti, Cr, Mo, Al,…)
![Page 14: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/14.jpg)
Catalytic ActivationCatalytic Activation
Surface ModificationSurface Modification
The Molecular Designed Dispersion
Support-OH+
VO(acac)2
Ligand Exchange
Hydrogen Bonding
Support
O
HH3C
H3C
CH3
CH3
CHHC
O
V
O
OO
O
O
O
V
O
HC
H3C
H3CO
Support
+ Hacac
Support-O-VOx
ADSORPTION CALCINATION
VO(acac)2 : Vanadylacetylacetonate
![Page 15: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/15.jpg)
Catalytic ActivationCatalytic Activation
Spectroscopic CharacterizationSpectroscopic Characterization
FTIR Spectroscopy
2800300032003400360038004000Wavenumber (cm-1)
Pho
to A
cous
tic S
igna
l (A
.U.)
Si-OH
H-bonding
V-OH
80010001200140016001800Wavenumber (cm-1)
Pho
to A
cous
tic S
igna
l (A
.U.)
acac
Si-O-V
Blank MCM
VO(acac)2 + MCM
VOx/MCM
![Page 16: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/16.jpg)
Catalytic ActivationCatalytic Activation
Spectroscopic CharacterizationSpectroscopic Characterization
FT-Raman
Raman frequency ~ V-O bond length~ VOx coordination
1042 cm-1 : (V=O) tetrahedral997 cm-1 : (V=O) octahedral
940980102010601100Raman Shift (cm-1)
Inte
nsit
y (A
.U.)
0.2 mmol/g
1.3 mmol/g
0.7 mmol/g
0.4 mmol/g
1042 cm-1 997 cm-1
v2o5
S
V
O
O OO
S S
• VOx/MCM catalysts < 1 mmol/g V :tetrahedrally coordinated VOx
• Raman spectroscopy is very sensitive towards micro-crystalline V2O5
![Page 17: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/17.jpg)
0
2
4
6
8
10
12
14
16
18
200 300 400 500Wavelength (nm)
Kub
elka
Mun
k U
nits
Catalytic ActivationCatalytic Activation
Spectroscopic CharacterizationSpectroscopic Characterization
VOx coordination Band position (nm)
tetrahedral isolated 250, 300tetrahedral 1D chains 350
square pyramidal 410octahedral 470
(a) 0.4 mmol/g V
(b) 0.7 mmol/g V
(c) 1.3 mmol/g V
OV charge transfer bands ~ VOx coordination
Progression of polymerisation as a function of the surface loading :
UV-VIS-DRS
(a) Isolated tetrahedral(b) isolated + 1D chains(c) isolated + chains + V2O5 crystals
![Page 18: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/18.jpg)
Catalytic ActivationCatalytic Activation
Catalytic PerformanceCatalytic Performance
Oxidation of methanol (at T = 400°C)
0
10
20
30
40
50
60
70
80
90
100
0.00 0.25 0.50 0.75 1.00 1.25 1.50
V (mmol/g)
Con
vers
ion
and
yiel
d (%
)
Conversion COx
Formaldehyde + dimethylether
Tetrahedral VOx :
activity increases with V loading high formaldehyde yield
Formation of V2O5 clusters :
activity decreases selectivity decreases drastically
![Page 19: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/19.jpg)
Catalytic ActivationCatalytic Activation
Catalytic PerformanceCatalytic Performance
Oxidation of methanol (at T = 400°C)On pure, grafted and incorporated VOx-MCM materials for different
vanadium loadings
ConvFA
DMECO
Blank
I ncorp (1 wt% V)
Graf ted (1 wt% V)
I ncorp (2.6 wt% V)
Graf ted (3 wt % V)
0
10
20
30
40
50
60
70
80
90
100Yi
eld
(%
)Acidic sites
Dimethylether (DME)
Basic sites
Carbonoxides (CO)
Redox sites
Formaldehyde (FA)
![Page 20: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/20.jpg)
Catalytic ActivationCatalytic Activation
Supported Mixed Oxide CatalystsSupported Mixed Oxide Catalysts
Synthesis of a new mixed oxide phase using the Molecular Designed Dispersion method :
Vanadium oxide + Tantalum oxide
Combining different oxide phases Synergy or complementary properties Improved catalytic performance
Structural characterization
FTIR, FT-Raman, UV-VIS-DRS
Surface properties
Adsorption of pyridineCatalytic performance
![Page 21: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/21.jpg)
Catalytic ActivationCatalytic Activation
Supported Mixed Oxide CatalystsSupported Mixed Oxide Catalysts
FT-RamanFTIR
S
V
O
O OO
S S
S
V
O
O OO
S SS
Ta
O
OO
SO
S
Ta
O
OO
SO
SS
S
V
O
O OO
S S
60070080090010001100
Wavenumber (cm-1)
Pho
to A
cous
tic S
igna
l (A
.U.)
1003005007009001100
Raman Shift (cm-1)
Inte
nsity
(A
.U.)
Ta=
OV
=O
Si-
O-V
Ta=
O
Si-
O-T
a
Blank
VOx
TaOx
VOx-TaOx
Well-mixed and well-dispersed
VOx-TaOx catalysts
![Page 22: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/22.jpg)
Catalytic ActivationCatalytic Activation
Supported Mixed Oxide CatalystsSupported Mixed Oxide Catalysts
Catalyst with active redox and active acid sites
Oxidation of methanol (at T = 250°C)
Redox siteVOx
Acid siteTaOx
+
VOx-TaOx
Redox site : formaldehyde, methylformateAcid site : dimethylether
Sel
ecti
vity
(%
)
(0.4 mmol/g)(0.2 mmol/g)
(0.4 mmol/g V + 0.2 mmol/g Ta)
VOxTaOx
VOx-TaOx
Formaldehyde
Methylformate
Dimethylether
0
10
20
30
40
50
60
70
80
90
100
![Page 23: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/23.jpg)
SBA-15 and SBA-16SBA-15 and SBA-16
Promising MaterialsPromising Materials
Qualities of SBA materials
Relatively large mesopores
Large amount of micropores
Thick pore walls
Incorporation of hetero-elements in thicker walls
Higher hydrothermal and mechanical stability
Use of non-toxic, biodegradable, non-ionic triblock copolymers as template
![Page 24: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/24.jpg)
0
200
400
600
800
1000
1200
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1
P/P0
Vo
lum
e (
cc
/g)
SBA-15 and SBA-16SBA-15 and SBA-16
A comparison with MCM-48A comparison with MCM-48
SBA-15SBA-16
MCM-48
5.03.01.4
1.30.61.0
9008001200
SBET
(m³/g)Vp
(ml/g)rp
(nm)
![Page 25: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/25.jpg)
Tuning pore size distribution Tuning pore size distribution
Pore size engineeringChanging synthesis conditions
size of surfactant
use of swellers
Synthesis temperature
![Page 26: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/26.jpg)
Size of surfactant
Length of EO blocks (ethyleneoxide) Characteristic for mesophase (structure)
Wall thickness
Triblock copolymers (pluronics) (EO)x(PO)y(EO)x
EO 4 units
17 - 37 units
132 units
lamellar
hexagonal
cubic
Length of PO blocks (propyleneoxide) influences porediameter
PO 30 units
70 units
3 nm ø
8 nm ø
Pore size engineering Pore size engineering
![Page 27: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/27.jpg)
Addition of swellers
(TMB, 1,3,5- trimethylbenzene)
0200400600800
10001200140016001800
0 0.2 0.4 0.6 0.8 1
P/P0
volu
me
ST
P (
ml/g
)
MCF SBA-15
0 50 100 150 200 250poreradius (Å)
Dv(
r)
Pore enlargement
mesocellular foam
MCF
Pore size engineering Pore size engineering
![Page 28: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/28.jpg)
In situ control of mesopore radius by changing the synthesis conditions using the same surfactant (EO70PO20EO70)
The SBA-15 materials were aged for 16 h at different temperatures:
Sample A = 75°C Sample B = 90°C Sample C = 105°C
A part of non calcined sample A had a hydrothermal treatment for 3 days at 100°C (Sample D)
A
BD
C
Pore size engineering Pore size engineering
0,00
0,02
0,04
0,06
0,08
0,10
0,12
0 20 40 60 80 100Pore Radius (Å)
Dv(
r)
![Page 29: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/29.jpg)
In situ control of micro/mesopore volume ratio by changing the synthesis conditions using the same surfactant (EO70PO20EO70)
Variable micro/mesopore volumeVariable micro/mesopore volume
Pore size engineering Pore size engineering
0
0,2
0,4
0,6
0,8
1
1,2
A D
pore
volu
me
(ml/g
)
microporevolume
mesoporevolume
Sample A: aged for 16h at 75°C Sample D: part of non calcined sample A after a hydrothermal treatment at 100°C for 3 days
![Page 30: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/30.jpg)
Morphologies of SBAMorphologies of SBA
1 micron
1 micronFibers of SBA
![Page 31: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/31.jpg)
Morphologies of SBAMorphologies of SBA
Spherical SBA
low µm range high µm range cm range
![Page 32: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/32.jpg)
Morphologies of SBAMorphologies of SBA
Growth mechanism of spherical SBA
![Page 33: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/33.jpg)
Catalytic activity of VOx and TiOx / SBA-15 in SCR of NO with ammonia.
DeNOx: 4 NO + 4 NH3 + O2 4 N2 + 6 H2O
0
20
40
60
80
100
100 200 300 400 500
Temperature (°C)
Co
nve
rsio
n / S
elec
tivi
ty (
%)
TiOx / SBA-15 VOx / SBA-15
0
20
40
60
80
100
100 200 300 400 500
Temperature (°C)
Co
nve
rsio
n / S
elec
tivi
ty (
%)
Not active below 350°C Not higher than 55% of conversion
Activation of SBA materials by MDD and Activation of SBA materials by MDD and Catalytic performanceCatalytic performance
Post-synthesis modificationPost-synthesis modification
![Page 34: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/34.jpg)
SBASBACatalytic performance Catalytic performance
Mixed oxide TiOx - VOx / SBA-15 catalyst
0
20
40
60
80
100
100 150 200 250 300 350 400
Temperature (°C)
Co
nve
rsio
n /
Sel
ecti
vity
(%
)
VOx - TiOx / SBA-15
• Very active in a low temperature range
•~100% NO conversion (above 250°C)•~100% N2 selectivity (all temp. range)
![Page 35: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/35.jpg)
Post-synthesis modifications
Simultaneous formation and activation
metal oxides nanoparticles
zeolite based nanoparticles
Related SBA materialsRelated SBA materials
In situ formation of amorphous siliceous
microporous nanoparticles
![Page 36: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/36.jpg)
0
100
200
300
400
500
600
700
0.0 0.2 0.4 0.6 0.8 1.0P/P0
volu
me
adso
rbed
gas
(m
l/g)
0
100
200
300
400
500
0.0 0.2 0.4 0.6 0.8 1.0P/P0
volu
me
adso
rbed
gas
(m
l/g)
open mesopores ink-bottle mesopores
SBA-15 and related materialsSBA-15 and related materials
PHTS PHTS
Typical N2 sorption isotherms (77K) for various SBA-15 materials
![Page 37: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/37.jpg)
PHTS (Plugged Hexagonal Templated Silica)
PHTSPHTS
0
100
200
300
400
500
600
0.0 0.2 0.4 0.6 0.8 1.0P/P0
volu
me a
dso
rbed
gas
(m
l/g)
Vmicropores
Vnarrowed meso
Vmeso open
![Page 38: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/38.jpg)
Post-synthesis modifications
Simultaneous formation and activation
metal oxides nanoparticles
zeolite based nanoparticles
Related SBA materialsRelated SBA materials
In situ formation of amorphous siliceous
microporous nanoparticles
![Page 39: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/39.jpg)
metal oxides nanoparticles (TiO2)
Related SBA materialsRelated SBA materials
tuneable sizetuneable crystal phase (rutile, anatase)tuneable number of active sitestuneable porous characteristics (size, number)
![Page 40: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/40.jpg)
Post-synthesis modifications
Simultaneous formation and activation
metal oxides nanoparticles
zeolite based nanoparticles
Related SBA materialsRelated SBA materials
In situ formation of amorphous siliceous
microporous nanoparticles
![Page 41: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/41.jpg)
TPAOH 20%
TEOS
VOSO4
nanoparticles zeolites (vanadiumsilicalite)
ageing 2 days
calcined SBA-15
acidification (HCl)
SBA-15 with zeolitic plugs inside the mesopores
Dry impregnation
SBA and related materialsSBA and related materials
Silicalite-1 nanoparticle depositionSilicalite-1 nanoparticle deposition
![Page 42: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/42.jpg)
Open mesopore
narrowed mesopore
Crystalline vanadiumsilicalite-1
nanoparticle
nanoparticles can be:
zeolitenanoparticles, metaloxides
microporous, non-porous
SBA and related materialsSBA and related materials
Silicalite-1 nanoparticle depositionSilicalite-1 nanoparticle deposition
![Page 43: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/43.jpg)
In situ synthesis strategies In situ synthesis strategies
Mesoporous materials with zeolite-like wallsMesoporous materials with zeolite-like walls
classic (vanadium) silicalite-1 synthesis mixture:
TPAOH, H2O and TEOS, (VOSO4)
clear solution containing nanoparticles
(vanadium) silicalite-1 zeolite
hydrothermal treatmentacidification: pH<1
silicalite-1-like nanoparticles with modified surfactant
hydrothermal treatmentNO TEMPLATE
mesoporous surfactant and refluxing
short range ordered mesoporous material
with tuneable porosity and hydrophobicity
long range ordered mesoporous materialswith ink-bottle pores
Mesoporous materials with silicalite-1-like wallsMesoporous materials with silicalite-1-like walls
![Page 44: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/44.jpg)
In situ synthesis strategies In situ synthesis strategies
Mesoporous materials with zeolite-like wallsMesoporous materials with zeolite-like walls
classic (vanadium) silicalite-1 synthesis mixture:
TPAOH, H2O and TEOS, (VOSO4)
clear solution containing nanoparticles
(vanadium) silicalite-1 zeolite
hydrothermal treatmentacidification: pH<1
silicalite-1-like nanoparticles with modified surfactant
hydrothermal treatmentNO TEMPLATE
mesoporous surfactant and refluxing
short range ordered mesoporous material
with tuneable porosity and hydrophobicity
long range ordered mesoporous materialswith ink-bottle pores
Mesoporous materials with silicalite-1-like wallsMesoporous materials with silicalite-1-like walls
![Page 45: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/45.jpg)
In situ synthesis strategies In situ synthesis strategies
Mesoporous materials with zeolite-like wallsMesoporous materials with zeolite-like walls
classic (vanadium) silicalite-1 synthesis mixture:
TPAOH, H2O and TEOS, (VOSO4)
clear solution containing nanoparticles
(vanadium) silicalite-1 zeolite
hydrothermal treatmentacidification: pH<1
silicalite-1-like nanoparticles with modified surfactant
hydrothermal treatmentNO TEMPLATE
mesoporous surfactant and refluxing
short range ordered mesoporous material
with tuneable porosity and hydrophobicity
long range ordered mesoporous materialswith ink-bottle pores
Mesoporous materials with silicalite-1-like wallsMesoporous materials with silicalite-1-like walls
![Page 46: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/46.jpg)
In situ synthesis strategies In situ synthesis strategies
Mesoporous materials with zeolite-like wallsMesoporous materials with zeolite-like walls
27002800290030003100
Raman Shift (cm -1)
Intensit
y
a
b
c
d
CH3
CH2
a) tripropylamine, b) TPAOH 20% solution, c) the full-grown VS-1 zeolite before calcination, d) SBA-VS-15 with acidified nanoparticles before calcinations
EPR and Raman show the loss of a ligand from the silicalite-1 template (TPAOH)
Consequences of acidifying the solution of vanadiumsilicalite-1 nanoparticle
14N
EPR HYSCORE spectra of SBA-VS with
acidified vanadium silicalite-1 nanoparticles
EPR HYSCORE spectra of full-grown vanadium silicalite-1
interaction of 14N with V
![Page 47: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/47.jpg)
In situ synthesis strategies In situ synthesis strategies
Mesoporous materials with zeolite-like wallsMesoporous materials with zeolite-like walls
Consequences of acidifying the solution of vanadiumsilicalite-1 nanoparticle
N
N+
V
=
V
O=
OSi
OO
O
HT
No mesotemplate
HCl
loss of n-propyl ligand stops the zeolite growth
N
N+N+
N+
![Page 48: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/48.jpg)
In situ synthesis strategies In situ synthesis strategies
Mesoporous materials with zeolite-like wallsMesoporous materials with zeolite-like walls
Consequences of acidifying the solution of vanadiumsilicalite-1 nanoparticle
hydrothermal treatmentNO TEMPLATE
Temp tuneable porosityTime tuneable porosity hydrophobicity
low pH growth of mesopores by edge-sharing (resembles sol-gel mechanism)
![Page 49: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/49.jpg)
ConclusionsConclusions
“Abracadabra” is a well-known incantation in the magic world, although the synthesis of tuned porous materials may still seem an art to many, it nonetheless can be understood to a certain level, appreciated and successfully performed.Making a white powder is by no means the end of the road in preparing porous materials; it is equally important to be able to characterize or to indentify, to engineer the porosity and to activate these materials that have been prepared for a desired application in sorption, catalysis and membranes.
![Page 50: Novel Synthesis and Activation strategies leading to the formation of tuned mesostructures.](https://reader036.fdocuments.in/reader036/viewer/2022062500/56649d6c5503460f94a4b609/html5/thumbnails/50.jpg)
AcknowledgementsAcknowledgements
* INSIDE PORES NoE
* University of Antwerpen: Prof. P. Cool Vera Meynen Wesley Stevens Liu Shiquan* I.A. Cuza University, Iasi, Romania: A. Busuioc A. Hanu