Immobilized Ru clusters in nanosized mesoporous zirconium silica for the aqueous hydrogenation of furan derivatives at room temperature

Article abstract of DOI:10.1002/cctc.201300316

Ru lonesome tonight? Immobilized ruthenium clusters (50Ru atoms) in nanosized mesoporous zirconium silica were synthesized by using an impregnation method starting from an aqueous solution of RuCl₃. The Ru cluster catalysts were thermally stable at 500°C and showed remarkable activity for the hydrogenation of furan derivatives in water at room temperature under 5bar hydrogen pressure.

Full text of DOI:10.1002/cctc.201300316

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Ru lonesome tonight? Immobilized
ruthenium clusters (50 Ru atoms) in
nanosized mesoporous zirconium silica
were synthesized by using an impregna-
tion method starting from an aqueous
J. Chen, F. Lu,* J. Zhang, W. Yu, F. Wang,
J. Gao, J. Xu*
&& – &&
Immobilized Ru Clusters in Nanosized
Mesoporous Zirconium Silica for the
Aqueous Hydrogenation of Furan
Derivatives at Room Temperature
solution of RuCl . The Ru cluster cata-
3
lysts were thermally stable at 5008C and
showed remarkable activity for the hy-
drogenation of furan derivatives in
water at room temperature under 5 bar
hydrogen pressure.
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DOI: 10.1002/cctc.201300316
Immobilized Ru Clusters in Nanosized Mesoporous
Zirconium Silica for the Aqueous Hydrogenation of Furan
Derivatives at Room Temperature
[a, b]
[a]
[a, b]
[a]
[a]
[a]
Jiazhi Chen,
Jie Xu*
Fang Lu,* Junjie Zhang,
Weiqiang Yu, Feng Wang, Jin Gao, and
[a]
[
9]
Noble-metal clusters are important catalysts because of their
unique structures and activities, which are associated with
synthesize valuable chemicals. Besides its nontoxic and non-
flammable properties, water is a desirable solvent because the
[
1]
[10]
their metalÀmetal bonds. Numerous methods have been de-
furan derivatives are soluble under aqueous conditions. Sev-
veloped to encapsulate metal clusters within porous materials
eral catalysts have been developed for the hydrogenation of
furan derivatives in water, but high reaction temperatures or
high hydrogen pressures are required to achieve high activities
[2]
or polymers to protect the clusters against sintering.
A
common porous support is zeolite, owing to its intrinsic sub-
nanometer pore diameters, which are similar to the size of the
metal clusters and can confine and prevent the clusters from
growing into big particles. This confinement allows metal clus-
ters to activate reactants with small molecular sizes that are ac-
[11]
because of the low aqueous solubility of hydrogen.
Herein, immobilized ruthenium clusters (50 Ru atoms) in
nanosized mesoporous zirconium silica (MSN-Zr) were synthe-
sized by using an impregnation method, starting from an
[
3]
cessible to the pores.
aqueous solution of RuCl . The Ru cluster catalyst showed re-
3
Mesoporous silica provides an ideal support, owing to its
large pore diameters, which are suitable for large-sized organic
markable activity for hydrogenation of furan derivatives in
water at room temperature under 5 bar hydrogen pressure.
MSN-Zr-x, which has a uniform hexagonal pore structure,
was synthesized by modification of our previously reported
[
4]
substrates and biomass derivatives. Ligand-stabilized metal
precursors are usually used to anchor the clusters within the
[5]
[12]
mesoporous channel with a low loading of the metal. Uni-
form mesoporous-silica-supported noble-metal clusters cannot
be achieved by impregnation of the support in an aqueous so-
lution of the metal salts because the pore diameter of meso-
porous silica (>2 nm) is larger than the size of the metal clus-
ters. The metal clusters are easily grown into big particles with
two-step procedure, in which x denotes the Si/Zr molar ratio
(for the detailed preparation, see the Supporting Information).
The morphology and pore structure are similar to those of
nanosized mesoporous silica (MSN), as shown in the Support-
ing Information, Figures S1 and S2. IR, UV, and energy-disper-
sive X-ray spectroscopy (EDS) measurements confirmed the in-
corporation of Zr into the mesoporous silica (see the Support-
ing Information, Figures S3–S5).
[
6]
a broad size distribution. The incorporation of heteroele-
ments (Zr, Ti, Al, etc.) into mesoporous silica has been devel-
[
7]
oped to disperse metal species. However, some metal parti-
cles still migrate towards the outside of the support during the
reduction step with hydrogen, which causes their aggregation
into big particles and, hence, the blocking of the entrance to
the pore channels. Therefore, substantial challenges remain to-
wards the goal of synthesizing uniform metal clusters that are
immobilized within mesoporous silica from the corresponding
metal salts.
Supported 5 wt.% Ru catalysts were synthesized by impreg-
nating the supports with an aqueous solution of RuCl , fol-
3
lowed by drying at 1108C in air and reducing in a flow of H at
2
3508C for 6 h. TEM images of Ru/MCM-41, Ru/MSN, Ru/MSN-
Zr-20, and Ru/MSN-Zr-20-C (after calcination in air) and their
corresponding particle-size distributions are shown in Figure 1.
The Ru nanoparticles that were supported on commercial
MCM-41 with long channels showed particle sizes that ranged
from 2.0 to 8.0 nm (Figure 1a), with an average size of 3.8 nm,
which was similar to the XRD results (see the Supporting Infor-
mation, Table S1). We found that smaller Ru nanoparticles were
grown inside the pores of MCM-41, whereas some larger parti-
cles were attached onto the outer part of the support (Fig-
ure 1a). Interestingly, if MSN with short channels was used, the
average particle size decreased to 1.6 nm. Moreover, most of
the Ru nanoparticles were highly dispersed (Figure 1b). How-
ever, some Ru nanoparticles escaped from the support, as
shown in the dashed circles in Figure 1b.
Biomass becomes an increasingly important feedstock to
[8]
produce fuels and chemicals for a sustainable future. Furan
derivatives have been identified as the key building blocks to
[
a] J. Chen, Dr. F. Lu, J. Zhang, W. Yu, Prof. F. Wang, Prof. J. Gao, Prof. J. Xu
Dalian National Laboratory for Clean Energy
State Key Laboratory of Catalysis
Dalian Institute of Chemical Physics
Chinese Academy of Sciences
4
57 Zhongshan Road, Dalian 116023 (P. R. China)
E-mail: lufang@dicp.ac.cn
xujie@dicp.ac.cn
If MSN-Zr was used, the average particle size further de-
[b] J. Chen, J. Zhang
[13]
creased to 1.1 nm. Calculations revealed that approximately
University of Chinese Academy of Sciences
50 Ru atoms were contained in a Ru cluster of size 1.1 nm.
1
9A Yuquan Road, Beijing 100049 (P. R. China)
Moreover, the Ru clusters were stabilized inside the channels,
that is, no escaped Ru clusters were found, as shown in Fig-
Supporting information for this article is available on the WWW under
http://dx.doi.org/10.1002/cctc.201300316.
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Figure 1. TEM images and particle-size distributions of a) 5 wt.% Ru/MCM-41, b) 5 wt.% Ru/MSN, c) 5 wt.% Ru/MSN-Zr-20, and d) 5 wt.% Ru/MSN-Zr-20-C.
Insets show HRTEM images of typical Ru clusters supported on MSN (b) and MSN-Zr (c).
ure 1c and the Supporting Information, S6. In addition, there is
no apparent loss of surface area compared to the original sup-
port (see the Supporting Information, Table S2), thus indicating
that the support channels are fully open to the reactants. After
calcination in air at 5008C for 3 h, the average particle size of
the Ru cluster was still 1.1 nm, thus confirming that the Ru
cluster in MSN-Zr was thermally stable (Figure 1d). These re-
sults suggest that the Ru clusters that are supported on MSN-
Zr are highly dispersed and stabilized inside the channel and
are accessible to the reactants.
Figure 2a shows a HAADF image of the MSN-Zr-supported
Ru catalysts. EDS element mapping of Si (Figure 2b), Zr (Fig-
ure 2c), and Ru (Figure 2d) was performed across interfaces
(rectangle 1). Most of the Ru elemental map could be over-
lapped with that of Zr, thus indicating that most of the Ru
clusters are attached around the enriched zirconium area.
To further study the chemical states of the Ru clusters and
the zirconium-silica support, the 3d core-level spectra of both
Ru and Zr were measured by in situ XPS. Figure 3a shows
a Ru 3d5/2 peak at 280.4 eV, which is assigned to metallic ruthe-
[14]
nium once the Ru/MSN precursors are reduced at 3508C.
The binding energy (BE) values of Ru 3d5/2 in the reduced Ru/
MSN-Zr-20 samples (280.9 eV) are slightly higher than that ob-
served in Ru/MSN. These spectroscopic data indicate a positive
charge on the ruthenium clusters, which results in the forma-
Figure 2. a) HAADF image of Ru/MSN-Zr nanospheres and EDS elemental
maps of b) Si, c) Zr, and d) Ru.
d+
[15]
tion of Ru species. On comparing the BE (Zr 3d5/2) value of
MSN-Zr-20 to that after hydrogen reduction, the peak appears
to be in the same state, as shown in Figure 3b. If ruthenium is
located on the support, the Zr 3d5/2 peak of Ru/MSN-Zr-20 is
shifted to higher binding energy by 0.9 eV. The variation in the
BE values indicates that the Ru clusters that are anchored onto
the MSN-Zr support are positively charged and induce the Zr
firm that there is a strong interaction between the Ru cluster
and the MSN-Zr support (see the Supporting Information, Fig-
[17]
d+
ure S7). From these results, we concluded that Ru species
and a new chemical environment around the Zr species were
formed on the Ru/MSN-Zr-20 catalysts.
The difference between commercial MCM-41 and MSN is the
channel length. We mimicked the impregnation process by
using capillary sizes of 1 and 10 cm. This difference appeared
after the drying process. There was a clear black deposition
[16]
in the supports to adopt a new chemical environment. The
H -TPR profiles of RuCl salt on different supports further con-
2
3
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inside the channel, instead of
undergoing deposition at the
channel mouth. After Zr was
added into the MSN, all of the
Ru ions were immobilized inside
the channel because of the
strong interactions between Ru
ions and the support. Thus, we
conclude that both short chan-
nels and zirconium oxide im-
prove the dispersion of Ru ions,
thus leading to the anchoring of
the ruthenium clusters inside the
mesoporous channels with high
dispersion and stability.
We performed the aqueous
hydrogenation of 5-hydrome-
thylfurfural (HMF) as a model re-
action over various supported
Ru and Ru-black catalysts with
different particle sizes (see the
Figure 3. In situ XPS studies of Ru/MSN, Ru/MSN-Zr-20, and MSN-Zr-20. a) Ru 3d spectra, which consist of Ru 3d5/2
and Ru 3d3/2 peaks. b) Zr 3d spectra, which consist of Zr 3d5/2 and Zr 3d3/2 peaks.
onto both ends of the long capillary, whereas the black deposi-
tion was more evenly distributed in the short capillary (see the
Supporting Information, Figure S8). Based on these observa-
tions, we proposed a mechanism to explain the effect of the
support on the size of the Ru clusters, as shown in Scheme 1.
Supporting Information, Table S1). Conversions and product se-
lectivities are listed in the Supporting Information, Table S3.
The impact of Ru particle size on the overall catalytic hydroge-
nation of HMF is shown in Figure 4. The rate of hydrogenation
of HMF increased slightly on decreasing the Ru particle size
from 14 to 2 nm. If the particle size was smaller than
2
nm, the rate of HMF hydrogenation increased dra-
matically. The rate of HMF hydrogenation at a particle
À1
size of 1.1 nm was 21 h , which was 34 times higher
[19]
than that at a particle size of 14.4 nm. Fujitani et al.
also reported that the hydrogen-dissociation activity
of an Au/TiO catalyst increased markedly if the Au
2
particle size was below 2 nm.
To understand the high activity of Ru clusters that
are smaller than 2 nm, the specific rate is introduced
to determine the number of moles of hydrogen mol-
ecules that react on each surface of the Ru cluster.
Figure 4, inset, shows that the specific rate increased
with decreasing size of Ru. This result indicates that
the remarkable increase in the hydrogenation rate
could not be exclusively attributed to a size effect. It
has been reported that an electron-deficient metal
cluster might form if the metal cluster is supported
[21]
on acidic surface sites or oxide entities. Electron
deficiency might only be the property of rather small
metal particles, because the positive charge would
be shared among hundreds of metal atoms with
Scheme 1. Proposed mechanism for the channel-length effect on the synthesis of the
supported Ru catalysts.
[15]
large particle sizes. Electron deficiency affects the
chemisorption and enhances the hydrogenation activity of the
We assumed that the surface concentration of the RuCl solute
3
[22]
was higher than that of the bulk solution, according to Gibbs’
metal clusters. The NH -TPD of MSN-Zr indicates there are
3
[
18]
surface-excess theory. The Ru ions would be continuously
deposited at the channel mouth during the drying process for
the long-channel commercial MCM-41. The short-channel sup-
port MSN could increase the evaporation of water, based on
thermogravimetric (TG) analysis, as shown in the Supporting
Information, Figure S9. Therefore, most of the Ru ions stay
acidic sites on the support surface (see the Supporting Infor-
mation, Figure S10) and the XPS analysis suggests that the
d+
Ru species are formed on the Ru/MSN-Zr catalysts. Therefore,
we presume that the supported Ru clusters on MSN-Zr
become electron deficient if the particle size is smaller than
2 nm. The high hydrogenation activity of 1.1 nm Ru clusters is
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Table 1. Hydrogenation of furan derivatives by using the Ru/MSN-Zr
[
a]
catalyst.
[
b]
[c]
R
Conversion [%]
Selectivity [%]
1
2
H
88.5
87.4
98.1
100
87.5
68.9
92.1
84.1
11.8
9.1
5.3
CH
CH
CH
3
2
2
OH
OC
2
H
5
12.5
À5
[
a] Reaction conditions: Substrate (0.1 g), Ru/MSN-Zr-10 (2.47ꢁ10 mol
2
Ru), water (9.9 g), 258C, H (5 bar), 4 h at 1000 rpm. [b] Conversions of
the furan derivatives. [c] Selectivities for the corresponding hydrogenated
products.
2
Figure 4. Plot of the turnover frequencies (TOFs), based on the H -consump-
tion rate, of HMF hydrogenation as a function of the size of the Ru particles
on various supports. The total TOFs were simply defined as the total moles
2
of H converted per mole of Ru per hour. Specific rate was defined as the
number of moles of hydrogen molecules that reacted at each surface per
hour; the total surface area of the Ru nanoparticles was determined by as-
suming a spherical shape.
[
20]
were accessible to substrates. The catalyst showed remarkably
high activity for the hydrogenation of furan derivatives in
aqueous solution at room temperature. The control of selectiv-
ity of the products on the Ru cluster catalyst could be ach-
ieved by simply adjusting the reaction temperature. We pro-
posed that the small size and electron deficiency of the Ru
clusters contributed to their high activity. The reusability ex-
periments and calcination tests showed that this catalyst was
very stable. Although the underlying mechanism of the high
thermal stability of Ru cluster on Ru/MSN-Zr is not yet fully
clear, it could lead to the development of a new group of
highly stable, practically relevant metal cluster catalysts.
not solely attributed to small size, but also to the electron-defi-
cient effect.
Control of the selectivity of the products on the Ru cluster
catalyst was also studied, as shown in the Supporting Informa-
tion, Figure S13. 2,5-Dihydroxymethylfuran (DHMF) is the main
product at a reaction temperature of 258C, whereas 1,2,5-hexa-
netriol (1,2,5-HT) becomes the main product on increasing the
[
10b]
temperature to 1008C. Conversely, Alamillo et al.
reported
that 1,2,5-HT was detected as a by-product if the aqueous hy-
drogenation of HMF over Ru/SiO was performed at 1308C. In
2
our catalytic system, the opening of the furan ring predomi-
nates, rather than the hydrogenation reactions of the aldehyde Experimental Section
or the furan ring, during the aqueous conversion of HMF at
Synthesis of the Ru-containing catalysts
high temperatures.
The synthesis of nanosized mesoporous zirconium silica (MSN-Zr-x,
in which x denotes the Si/Zr molar ratio) was performed by modifi-
cation of our reported method. The detailed procedure is de-
scribed in the Supporting Information, Section S1. A series of sup-
ported Ru catalysts were typically prepared by impregnating the
After the aqueous hydrogenation reaction (258C, 5 bar H2,
h), the Ru/MSN-Zr catalyst was separated from the reaction
4
[12]
mixture by centrifugation and this catalyst was reused in sub-
sequent runs under identical reaction conditions; the results
are shown in the Supporting Information, Figure S14. The cata-
lytic conversion of HMF was still observed after five cycles. Im-
portantly, TEM analysis of the Ru catalyst after the fifth run in-
dicated that the mesoporous structure of the support and the
particle size of the Ru cluster remained unchanged.
supports with an aqueous solution of RuCl , followed by drying in
3
air at 1108C and reduction in a flow of H at 3508C for 6 h. Ru/
2
MSN-Zr-20 was also calcined in air at 5008C for 3 h to estimate the
thermal stability of the supported Ru clusters, denoted as Ru/MSN-
Zr-20-C. Ru black (Strem Chemicals, 99.9%), which was used for
the control reactions, was activated under different conditions,
The use of the Ru cluster catalyst was further extended to
the hydrogenation of a series of furan derivatives, including
furfural, 5-ethoxymethyl-2-furfural (EMF), and 5-methyl-2-furfu-
ral (MFF, Table 1). These four furan derivatives were hydrogen-
ated into furan alcohol and tetrahydrofuran alcohol at room
temperature with high activities. These results show that Ru
cluster catalyst has high activity for the hydrogenation of furan
derivatives in water at room temperature.
that is, it was reduced in a flow of H at 2008C for 2 h (denoted as
2
Ru black-200) or calcined at 5008C under a N atmosphere for 3 h
2
and subsequently reduced in a flow of H at 3508C for 6 h (denot-
2
ed as Ru black-500).
Characterization
The particle size and shape were analyzed by TEM on a JEM-
In conclusion, we have immobilized uniform Ru clusters
within nanosized mesoporous zirconium silica with 5 wt.% Ru
loading by using an impregnation method starting from an
2
000EX microscope that was operated at 120 kV. The micromor-
phology and composition of Ru/MSN and Ru/MSN-Zr were deter-
2
mined on a FEI Tecnai G F30 S-Twin microscope from HRTEM and
aqueous solution of RuCl . These Ru clusters were highly dis-
HAADF images and elemental maps. In situ XPS spectra for the
chemical states of ruthenium and zirconium were recorded on
3
persed and stabilized within the mesoporous channels and
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a VGESCALAB MK2 spectrometer by using AlKa radiation (Ehu
=
Okatsu, T. Akita, T. Takei, M. Haruta, Angew. Chem. 2008, 120, 9405–
9
408; Angew. Chem. Int. Ed. 2008, 47, 9265–9268.
2] a) A. Kulkarni, R. J. Lobo-Lapidus, B. C. Gates, Chem. Commun. 2010, 46,
997–6015; b) F. Lu, J. Liu, J. Xu, Adv. Synth. Catal. 2006, 348, 857–861.
3] S. Goel, Z. Wu, S. I. Zones, E. Iglesia, J. Am. Chem. Soc. 2012, 134,
7688–17695.
4] Y. L. Huang, S. Xu, V. S. Y. Lin, Angew. Chem. 2011, 123, 687–690; Angew.
Chem. Int. Ed. 2011, 50, 661–664.
[5] a) D. J. Mihalcik, W. B. Lin, Angew. Chem. 2008, 120, 6325–6328; Angew.
Chem. Int. Ed. 2008, 47, 6229–6232; b) E. Serrano, N. Linares, J. Garcia-
Martinez, J. R. Berenguer, ChemCatChem 2013, 5, 844–860.
1
486.6 eV) operated at 12.5 kV and 250 W as the excitation source.
[
[
[
The temperature-programmed reduction of hydrogen (H -TPR) and
2
5
the temperature-programmed desorption of ammonia (NH -TPD)
3
were recorded on a Micromeritics Autochem II 2920 instrument
that was equipped with a thermal conductivity detector (TCD) and
an on-line mass detector. XRD patterns were performed on
a Rigaku D/Max 2500PC diffractometer with CuKa radiation (l=
1
1
.5418 ꢂ) and used for calculating the Ru particle sizes based on
the Scherrer equation. Nitrogen-physisorption experiments were
performed on a Quantachrome Autosorb-1 apparatus at À1968C.
To identify the incorporation of zirconium ions into the MSN frame-
work, the as-synthesized MSN and MSN-Zr materials were charac-
terized by FTIR spectroscopy and diffuse-reflectance UV/Vis spec-
troscopy (UV/Vis DRS).
[
[
6] C. H. Yen, H. W. Lin, C.-S. Tan, Catal. Today 2011, 174, 121–126.
7] a) A. K. Sinha, S. Seelan, S. Tsubota, M. Haruta, Angew. Chem. 2004, 116,
1
572–1574; Angew. Chem. Int. Ed. 2004, 43, 1546–1548; b) D. Liu, X. Y.
Quek, W. N. E. Cheo, R. Lau, A. Borgna, Y. Yang, J. Catal. 2009, 266, 380–
90.
8] a) M. S. Holm, S. Saravanamurugan, E. Taarning, Science 2010, 328, 602–
05; b) T. S. Hansen, K. Barta, P. T. Anastas, P. C. Ford, A. Riisager, Green
3
[
6
Chem. 2012, 14, 2457–2461; c) D. Z. Zhang, R. Al-Hajri, S. A. I. Barri, D.
Chadwick, Chem. Commun. 2010, 46, 4088–4090; d) Z. W. Huang, F. Cui,
H. Kang, J. Chen, X. Z. Zhang, C. G. Xia, Chem. Mater. 2008, 20, 5090–
Hydrogenation of the furan derivatives
The catalytic activity of the Ru catalysts was studied by using the
aqueous hydrogenation of 5-hydroxymethylfurfural (HMF) as
a model reaction. The reactions were performed in a 50 mL auto-
clave (T316 Stainless Steel, ASME SA-479, Parr Instrument) under
5099; e) J. N. Chheda, G. W. Huber, J. A. Dumesic, Angew. Chem. 2007,
119, 7298–7318; Angew. Chem. Int. Ed. 2007, 46, 7164–7183.
[
9] a) T. Buntara, S. Noel, P. H. Phua, I. Melian-Cabrera, J. G. de Vries, H. J.
Heeres, Angew. Chem. 2011, 123, 7221–7225; Angew. Chem. Int. Ed.
2011, 50, 7083–7087; b) P. H. Che, F. Lu, J. J. Zhang, Y. Z. Huang, X. Nie,
J. Gao, J. Xu, Bioresour. Technol. 2012, 119, 433–436; c) J. Ma, Z. Du, J.
Xu, Q. Chu, Y. Pang, ChemSusChem 2011, 4, 51–54; d) Z. T. Du, J. P. Ma,
F. Wang, J. X. Liu, J. Xu, Green Chem. 2011, 13, 554–557.
[10] a) Y. Y. Gorbanev, S. K. Klitgaard, J. M. Woodley, C. H. Christensen, A. Riis-
ager, ChemSusChem 2009, 2, 672–675; b) R. Alamillo, M. Tucker, M.
Chia, Y. Pagꢃn-Torres, J. A. Dumesic, Green Chem. 2012, 14, 1413–1419.
an initial H pressure of 5 bar at 258C. After the reaction, the Ru/
2
MSN-Zr catalyst was centrifuged from the solution, washed with
water, and reused four more times. The reaction temperature and
other furan derivatives were also considered. The products were
1
13
identified by GCMS and by H NMR and C NMR spectroscopy. An
Angilent 7890A gas chromatograph system that was equipped
with an Angilent 19091j-323 capillary column (30 mꢁ530 mmꢁ
[
11] a) Y. Nakagawa, K. Tomishige, Catal. Commun. 2010, 12, 154–156; b) V.
Schiavo, G. Descotes, J. Mentech, Bull. Soc. Chim. Fr. 1991, 128, 704–
1
.5 mm) was used for product quantification. The measured reac-
tion rates, in units of hydrogen that was consumed, as derived
from the products per mole of Ru per hour, are reported as the
total TOFs. The surface-specific hydrogenation rate is estimated by
assuming that the Ru nanoparticles have a spherical shape and the
deduced equations are listed in the Supporting Information,
Section S2.
7
11.
[12] F. Lu, S. H. Wu, Y. Hung, C. Y. Mou, Small 2009, 5, 1408–1413.
[13] C. X. Xiao, Z. P. Cai, T. Wang, Y. Kou, N. Yan, Angew. Chem. 2008, 120,
758–761; Angew. Chem. Int. Ed. 2008, 47, 746–749.
[
14] Y. V. Larichev, B. L. Moroz, V. I. Bukhtiyarov, Appl. Surf. Sci. 2011, 258,
541–1550.
1
[
[
15] A. Y. Stakheev, L. M. Kustov, Appl. Catal. A 1999, 188, 3–35.
16] J. Wang, Y. Wang, S. Xie, M. Qiao, H. Li, K. Fan, Appl. Catal. A 2004, 272,
2
9–36.
Acknowledgements
[
17] D. Eliche-Quesada, E. Rodriguez-Castellon, A. Jimenez-Lopez, Micropo-
rous Mesoporous Mater. 2007, 99, 268–278.
We acknowledge financial support for the National Natural Sci-
ence Foundation of China (21233008, 21103174, and 21203183),
the Hundred Talents Program of the Dalian Institute of Chemical
Physics (DICP), and the State Key Laboratory of the Catalysis Pro-
gram of the DICP (R201110).
[18] A. W. Adamson, A. P. Gast, Physical Chemistry of Surfaces, 6th ed., Wiley-
VCH, New York, 1997, pp. 71–76.
[
19] T. Fujitani, I. Nakamura, T. Akita, M. Okumura, M. Haruta, Angew. Chem.
009, 121, 9679–9682; Angew. Chem. Int. Ed. 2009, 48, 9515–9518.
2
[
20] J. Chou, N. R. Franklin, S. H. Baeck, T. F. Jaramillo, E. W. McFarland, Catal.
Lett. 2004, 95, 107–111.
[
[
21] Z. C. Zhang, B. C. Beard, Appl. Catal. A 1999, 188, 229–240.
22] J. Lu, P. Serna, C. Aydin, N. D. Browning, B. C. Gates, J. Am. Chem. Soc.
2011, 133, 16186–16195.
Keywords: biomass · cluster compounds · hydrogenation ·
mesoporous materials · ruthenium
[
1] a) J. Oliver-Meseguer, J. R. Cabrero-Antonino, I. Dominguez, A. Leyva-
Perez, A. Corma, Science 2012, 338, 1452–1455; b) P. Serna, B. C. Gates,
J. Am. Chem. Soc. 2011, 133, 4714–4717; c) T. Ishida, N. Kinoshita, H.
Received: April 26, 2013
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