clusters in solid matrices.Supporting Information Wet ... fileS1 Supporting Information Wet synthesis and quantification of ligand–free sub–nanometric Au clusters in solid matrices.
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S1
Supporting Information
Wet synthesis and quantification of ligand–free sub–nanometric Au
clusters in solid matrices.
Judit Oliver–Meseguer,a Irene Dominguez,b Rafael Gavara,b Antonio Doménech-
Carbó,c J. M. González–Calbet,d Antonio Leyva–Pérez,a* and Avelino Corma.a*
a Instituto de Tecnología Química. Universidad Politécnica de Valencia–Consejo Superior de Investigaciones Científicas. Avda. de los Naranjos s/n, 46022, Valencia, Spain.
b Packaging Lab, Instituto de Agroquímica y Tecnología de Alimentos, IATA-CSIC, Av.
Leaching studies. Two parallel reaction mixtures were followed by GC, taking aliquots
periodically, under typical reaction conditions and one of them was filtered at a
determined conversion through a 0.2 µm PTFE filter. The resulting filtrates were placed
under the same conditions (stirring and temperature) that the original reaction and also
followed by GC.
S6
Figures.
94 92 90 88 86 84 82 80 78 76
100
150
200
250
300
350
400
CPS
BE (eV)
Reduced under H2
Reduced with phenylethanol Au 0 Au 3+ Au+ Au Au+
Figure S1. XPS spectrum of a sample of Au-nCeO2 after hydrogenation of 1 g of Au chloride
on nceria at 200-300 ºC under a flow of 100 ml per min of N2:H2 (10:1) (black line). The
percentage of cationic Au in the reduced sample is 15% after deconvolution. For comparison, a
sample of Au-nCeO2 with a stronger reduction treatment –1 g of Au chloride on ceria with 5 ml
of phenylethanol at 160 ºC for 1 h (green line)– is also presented. The percentage of cationic Au
decreases significantly to 2%.
2200 2000
Abso
rban
ce
Wavenumber (cm-1)
Au/CeO2 (red. with H2 vs. phenylethanol)
2160 2130 2109AuoAuinterphase
Au+
IR-CO (-176 ºC)
Figure S2. CO–IR of the Au–CeO2 sample prepared by hydrogenation at 200 ºC. The presence of cationic Au not present in the interphase is clearly seen. For comparison, the sample of Au–CeO2 reduced with phenylethanol shows only cationic Au in the interphase.
Isolated atoms, cluster or NPs?
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0.0 -0.4 -0.8 -1.2
E (V vs. AgCl/Ag)
1 μA
a)
b)
Au+ + xe- Au(-x)+
Au(-x)+ + (-x)e- Au
Figure S3. Linear potential scan voltammograms at glassy carbon electrodes modified with films of: a) pristine Au–nCeO2; and b) Au–nCeO2 reduced at 200 ºC in H2/N2 atmosphere, immersed into air–saturated 0.1 M aqueous NaOH. The plotted curves were obtained after subtracting the corresponding voltammogram for nanoparticulated ceria. Potential scan rate 20 mV/s.
300 400 500 600 700
Refle
ctan
ce (a
. u.)
(nm)
Figure S4. Left: A typical HR-TEM image of Au-nCeO2 solids. Only nanometric Au particles
can be distinguish and not sub-nanometric particles or isolated Au cations. Right: Reflectance-
diffuse UV-vis spectrum of nCeO2, which avoids the detection of any absorption band of Au
clusters.
S8
Figure S5. Reaction test for the Au-nCeO2 sample reduced at 200 ºC under hydrogen, see main text for reaction conditions.
Figure S6. Left: TOF0 (h-1) values in the reaction test for different Au-nCeO2 samples after
different reductive treatments, including a commercial sample reduced at 200 ºC under
hydrogen and nCeO2 impregnated with 15% neat Au3-7 clusters in aqueous solution. See main
text for reaction conditions. Right: Linear correlation for the different Au-nCeO2 solids between
TOF values in the reaction test and amount of cationic Au found by quantitative XPS
measurements.
Au-nCeO2 red. with phenylethanol
Au-nCeO2 red. at 500ºC
Au-nCeO2 red. at 200ºC
Au-nCeO2 comercial
Au clusters-CeO2
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0
20
40
60
80
100
0 5 10 15 20
Yiel
d of
4(%
)
Time (h)
D)
0
20
40
60
80
100
0 5 10 15 20
Yiel
d of
4 (%
)
Time (h)
C)
Figure S7. Leaching during the reaction test for Au-nCeO2 reduced at 200 ºC under hydrogen (left) and Au-Al2O3 (right).
OHCl
O+
O
O
O
O
O
5
A)
B)
Au@EVOH(0.01 mol%)
iPrOH:H2O (2:1)25 ºC
2 ( 2 eq)1
3
or
5
5
4
0 5 10 15 20 25
0
20
40
60
80
Con
vers
ion
(%)
Time (h)
Figure S8. Kinetic plot for the reaction test catalyzed by Au@EVOH, either starting from acyl
chloride 1 and propargylic alcohol 2 (squares) or from propargylic ester intermediate 3 (circles).
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200 300 400 500 600 700 800-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
Abs
orba
nce
(a. u
.)
(nm)
Figure S9. Top: Zetasizer measurement for Au@EVOH. Bottom: UV-vis Au@EVOH after
disaggregation
0
5
10
15
20
25
30
0 5 10 15
Prob
abili
ty <
1 nm
(%)
Average particle size measured by TEM (nm)
Transition metaloxide
Rare earth metaloxides
Carbonaceous
Aluminosilicates
0
5
10
15
20
25
30
35
0 5 10 15
Prob
abili
ty <
1 nm
(%)
Average particle size measured by TEM (nm)
Transition metaloxide
Rare earth metaloxides
Carbonaceous
Aluminosilicates
Figure S10. Normal (left) and lognormal (right) distributions for 30 different Au-supported
catalysts described in the literature (see main text) as a function of the average particle size
found by TEM.
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05
101520
2 3 4 5 >6
nº n
anop
artic
les
diameter (nm)
Figure S11. Transmission Electron Microscopy (TEM) image (left) and histogram of different samples (right) for Au–TiO2.
0 5 10 15 20 25-10
0
10
20
30
40
50
60
70
80
Au-Al2O3 Commercial DCM H2O
Conv
ersio
n (%
)
Time (h)
0 5 10 15 20 25
0
10
20
30
40
50
Au-TiO2 Commercial DCM H2O
Conv
ersio
n (%
)
Time (h)
0 5 10 15 20 25
0
20
40
60
80
Au-ZnO Commercial DCM H2O
Conv
ersio
n (%
)
Time (h)
Au loading: 1.5 wt%.
Average nanoparticle size: 4.3 nm.
Figure S12. Reaction test starting from compound 3 for Au-Al2O3, Au-TiO2 and Au-ZnO catalysts after being treated with I2 solutions in water.