Efficient Hydrogen Production from Methanol Using a Single-Site Pt1/CeO2 Catalyst

Article abstract of DOI:10.1021/jacs.9b09431

Hydrogen is regarded as an attractive alternative energy carrier due to its high gravimetric energy density and only water production upon combustion. However, due to its low volumetric energy density, there are still some challenges in practical hydrogen storage and transportation. In the past decade, using chemical bonds of liquid organic molecules as hydrogen carriers to generate hydrogen in situ provided a feasible method to potentially solve this problem. Research efforts on liquid organic hydrogen carriers (LOHCs) seek practical carrier systems and advanced catalytic materials that have the potential to reduce costs, increase reaction rate, and provide a more efficient catalytic hydrogen generation/storage process. In this work, we used methanol as a hydrogen carrier to release hydrogen in situ with the single-site Pt₁/CeO₂ catalyst. Moreover, in this reaction, compared with traditional nanoparticle catalysts, the single site catalyst displays excellent hydrogen generation efficiency, 40 times higher than 2.5 nm Pt/CeO₂ sample, and 800 times higher compared to 7.0 nm Pt/CeO₂ sample. This in-depth study highlights the benefits of single-site catalysts and paves the way for further rational design of highly efficient catalysts for sustainable energy storage applications.

Full text of DOI:10.1021/jacs.9b09431

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Communication
Efficient Hydrogen Production from Methanol
Using A Single-Site Pt1/CeO2 Catalyst
Lu-ning Chen, Kai-Peng Hou, Yi-Sheng Liu, Zhi-yuan Qi, Qi Zheng, Yi-Hsien Lu, Jia-yu Chen, Jeng-Lung
Chen, Chih-Wen Pao, Shuo-bo Wang, Yao-bin Li, Shao-hua Xie, Fu-Dong Liu, David Prendergast, Leonard
E Klebanoff, Vitalie Stavila, Mark D. Allendorf, Jinghua Guo, Lan-Sun Zheng, Ji Su, and Gabor A. Somorjai
J. Am. Chem. Soc., Just Accepted Manuscript • DOI: 10.1021/jacs.9b09431 • Publication Date (Web): 24 Oct 2019
Downloaded from pubs.acs.org on October 25, 2019
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Efficient Hydrogen Production from Methanol Using A Single-Site
Pt1/CeO2 Catalyst
Lu-Ning Chen,1,2 Kai-Peng Hou,1,3 Yi-Sheng Liu,5 Zhi-Yuan Qi,1 Qi Zheng,1 Yi-Hsien Lu,1 Jia-Yu
Chen,2 Jeng-Lung Chen,6 Chih-Wen Pao,6 Shuo-Bo Wang,1Yao-Bin Li,7 Shao-Hua Xie,8 Fu-Dong
Liu,8 David Prendergast,4 Leonard E. Klebanoff,9 Vitalie Stavila,9 Mark D. Allendorf,9 Jinghua
Guo,5 Lan-Sun Zheng,2 Ji Su,*,1,4 Gabor A. Somorjai*,1,3
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5
Materials Sciences Division, Molecular Foundry, Material Science Division, Advanced Light Source, Lawrence
Berkeley National Laboratory, Berkeley, California 94720, United States.
2
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for
Energy Materials, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University,
Xiamen 361005, China.
3 Department of Chemistry, University of California-Berkeley, Berkeley, California 94720, United States.
6 National Synchrotron Radiation Research Center, Science-Based Industrial Park Hsinchu 30076, Taiwan.
7 Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
8
Department of Civil, Environmental, and Construction Engineering, Catalysis Cluster for Renewable Energy and
Chemical Transformations (REACT), Nano-Science Technology Center (NSTC), University of Central Florida,
Orlando, Florida, 32916, United States.
9 Sandia National Laboratories, Livermore, CA 94551, United States.
Supporting Information Placeholder
In order to reduce atmospheric pollution and greenhouse
gas emission, developing clean energy sources has attracted
growing interest. Among them, hydrogen is desirable as an
alternative clean fuel, because it can be converted efficiently
to energy without producing toxic products or greenhouse
gases.[1] Nowadays, hydrogen is widely used in different fields,
especially in polymer electrolyte membrane fuel cells
(PEMFCs) due to its high gravimetric energy density (120
MJ/kg).[2] In contrast to other hydrogen transportation and
storage approaches, such as compressed gas, or solid-state
storage in metal hydrides and metal-organic frameworks
(MOFs),[3,4] the liquid organic hydrogen carriers (LOHCs)
concept involves transportation of hydrogen in liquids, and
generating hydrogen in situ by breaking chemical bonds,
often times in the presence of a catalyst.[5,6] There are
advantages to transporting and handling liquids, such as
added safety, greater energy density, and possibility of
utilizing the existing gasoline and oil infrastructure and
reduced costs overall.
ABSTRACT: Hydrogen is regarded as an attractive alternative
energy carrier due to its high gravimetric energy density and
only water production upon combustion. However, due to its
low volumetric energy density, there are still some challenges
in practical hydrogen storage and transportation. In the last
decade, using chemical bonds of liquid organic molecules as
hydrogen carriers to generate hydrogen in situ provided a
feasible method to potentially solve this problem. Research
efforts on liquid organic hydrogen carriers (LOHCs) seek
practical carrier systems and advanced catalytic materials that
have the potential to reduce costs, increase reaction rate, and
provide
a
more
efficient
catalytic
hydrogen
generation/storage process. In this work, we used methanol as
a hydrogen carrier to release hydrogen in situ with the single-
site Pt1/CeO2 catalyst. Moreover, in this reaction, compared
with traditional nanoparticle catalysts, the single site catalyst
displays excellent hydrogen generation efficiency, 40 times
higher than 2.5 nm Pt/CeO2 sample, and 800 times higher
compared to 7.0 nm Pt/CeO2 sample. This in-depth study
highlights the benefits of single-site catalysts and paves the
way for further rational design of highly efficient catalysts for
sustainable energy storage applications.
For practical applications, a key factor is to look for an
appropriate liquid organic molecule as hydrogen carrier.[7]
Compared to other liquid organic molecules, methanol is a
suitable molecule with high hydrogen gravimetric density.
Moreover, methanol is relatively inexpensive and can be
manufactured from
a variety of sources which can
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Page 2 of 6
transformed from some harmful gas or greenhouse gases like
Moreover, from corresponding elemental mapping, the Pt
signals are uniformly distributed overall CeO2 nanorods
(Figure 1b). In order to further confirmed the actual Pt loading
information on CeO2, the HAADF-STEM measurement was
applied. As shown in Figure 1a, the Pt catalytic sites were
atomically dispersed throughout the porous CeO2, and the
actual Pt content was 0.15%.
CO, CO2 and CH4.[8,9] In addition, seeking an efficient catalyst
to in situ generate large quantity of hydrogen in a short time
is another significant factor. In catalytic hydrogen production,
the traditional support metal catalysts typically need high
temperature and high metal loadings to achieve a relatively
good catalytic performance.[10] As previously studied, the size
of metal particles is critically important in determining the
performance of metal supported catalysts in many catalytic
reactions.[11,12] Moreover, the ultimate small-size limit for
particles is the single-site catalyst with isolated single metal
sites dispersed on solid supports. With maximum atom-
utilization efficiency (100 %), high specific activity and unique
properties can be realized, single-site catalysts are emerging
as a new frontier in catalytic science.[13-17]
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Herein, we successfully synthesized single-site Pt1/CeO2
catalyst with single Pt sites anchored on porous CeO2
supported by a modified ascorbic acid (AA)-assisted reduction
route.[18-19] In the catalytic hydrogen production from
methanol, compared with traditional Pt nanoparticles
catalysts (2.5 nm Pt/CeO2, 7.0 nm Pt/CeO2), this single-site
catalyst performed high activity at relative low temperature
with low Pt loading. Additionally, this single-site catalyst can
be applied to other alcohol catalytic hydrogen production.
In our study, porous CeO2 nanorods (Figure S1) were chosen
as the support to anchor Pt single atoms by AA-assisted
reduction route, named Pt1/CeO2. Meanwhile, we also
synthesized Pt nanoparticles with different sizes and loadings
on CeO2 by pre-synthesizing Pt nanoparticles and mixing
them with CeO2, and the capping agent on Pt surface was
[20,21]
further removed by UV-ozone treatment.
The loading
amounts of Pt are both were about 1% wt. For convenience,
the Pt nanoparticles loaded on CeO2 are named 2.5 nm
Pt/CeO2 and 7.0 nm Pt/CeO2, whose sizes are determined by
TEM measurement (Figure S2).
Figure 2. (a) k3-weighted Fourier transform EXAFS spectra and
(b) normalized XANES spectra of Pt1/CeO2 and bulk Pt foil at
the Pt L3-edge. The red hollow points are fitting results.
Extended X-ray absorption fine structure (EXAFS) spectra
were acquired to provide the valence and coordinated
structure of single-site Pt1/CeO2 catalyst. Compared with bulk
Pt foil there is no neared neighbor Pt-Pt bond observed in the
single-site Pt1/CeO2 catalyst, while the notable peak observed
between 1 to 2 Å is attributed to contribution of Pt-O bond
(Figure 2). The Pt dispersion states for the three samples are
further verified by in situ DRIFTs of CO absorption and
desorption (Figure S5). For the single-site Pt1/CeO2 catalyst,
three bands are observed, of which the bands at 2171 and 2117
cm-1 are attributed to the CO gas, while that at 2090 cm-1 are
attributed to the linearly (on-top) bonded CO on Pt ionic
species.[13, 18] However, for 2.5 nm Pt/CeO2 and 7.0 nm Pt/CeO2
there is another band on at 2050 cm-1 due to the linear
absorbance of CO on the small sized Pt nanoparticles on
Figure 1. (a) Cs-corrected high-angle annular dark-field
scanning transmission electron microscopy (HAADF-STEM)
images of Pt1/CeO2 catalyst, the brighter dots cycled are Pt
single sites, (b) HAADF-STEM and corresponding elemental
mappings images of Pt1/CeO2 catalyst.
The loading status of Pt loading on CeO2 catalysts were
compared by powder X-ray diffraction (XRD) and
transmission electron microscope (TEM). From the XRD data,
there are no diffraction peaks observable from metallic Pt for
all the three catalysts due to the low Pt content and small Pt
particle sizes (Figure S3). In the bright-field TEM images of 2.5
nm Pt/CeO2 and 7.0 nm Pt/CeO2, the Pt nanoparticles are
uniformly dispersed on CeO2 nanorods (Figure S4b, c).
However, for Pt1/CeO2 catalyst there is no apparent difference
compared to original CeO2 nanorods (Figure S1a), with no
metallic clusters or particles being observed (Figure S4a).
[13,22]
CeO2.
In the direct methanol catalytic hydrogen production,
compared with traditional Pt nanoparticles (2.5 nm Pt/CeO2
and 7.0 nm Pt/CeO2), the single-site Pt loaded on CeO2
(Pt1/CeO2) displayed excellent catalytic performance (Figure
o
3a). At the temperature below 150 C, both the Pt single-site
and Pt nanoparticle catalysts have no obviously catalytic
o
activity. As the temperature was increased to above 150 C,
both the formation of hydrogen and carbon monoxide were
detected. Further increasing the reaction temperature, more
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methanol was converted to hydrogen and carbon monoxide.
both O-H and C-H bond cleavage, much lower on the defects
and steps of the Pt surface.
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Moreover, due to the size effect, the single-site Pt1/CeO2
catalyst performed with higher activity for hydrogen
production from methanol than the 7.0 nm Pt/ CeO2 and 2.5
nm Pt/CeO2 counterparts. The turnover frequency (TOF) of
Pt1/CeO2 catalyst is much higher than traditional Pt
nanoparticle, up to 12500 h-1 at 300 oC, which is 40 times that
of 2.5 nm Pt/CeO2 and almost 800 times that of 7.0 nm
Pt/CeO2. Furthermore, the single-site Pt1/CeO2 sample is
highly stable: after reaction at 300 oC for 120 hours, the catalyst
keeps more than 90% of its best activity (Figure 3b). The
decrease of activity at initial times is due to the loss of unstable
absorb Pt sites on CeO2 surface. The Pt content of Pt1/CeO2
catalyst decreased to 0.13% after the first 10 hours of reaction
and thereafter remains almost the same after 120 hours
reaction. After long-time reaction, there is still no Pt-Pt bond
detected by EXAFS (Figure S6) indicating there is no
agglomeration happened even after long-time reaction at 300
oC.
We also measured the catalytic hydrogen production
performance of single-site Pt1/CeO2 catalyst as a function of
the methanol feeding rate (Figure S7). At lower methanol
feeding rate, the conversion of methanol is higher. When the
feeding rate is 0.01 ml/min, methanol can totally convert to
hydrogen, which proves that this catalyst can be applied in
practical applications. As the feeding rate of methanol is
increased, the TOF increases as well. The TOF is almost 15000
h-1 at the feeding rate of 0.1 ml/min, illustrating the high
catalytic activity of Pt1/CeO2 catalyst. We as well synthesized
a series of Pt1/CeO2 catalysts with different Pt content by
controlling the feeding amount of Pt precursor (Figure S8a).
And all the Pt/CeO2 catalysts performed high activity in
methanol dehydrogenation. However, the TOF decrease of
Pt/CeO2-0.3% and 0.45%, due to Pt agglomeration at higher
content (Figure S8b). No hydrogenation formation was
detected with pure CeO2 nanorods without Pt loading,
indicating that the active site is Pt instead of CeO2.
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Single-site catalysts are typically systems where the activity
of a central metal atom/atoms relies on interactions with
heteroatomic ligands (such as N or O bridge) that anchor it to
metal atoms of the substrate. The electronic structure and
reactivity of Pt are very sensitive to support. In our study, the
Pt element valence states was proven to be another factor
influencing its catalytic activity. The Pt and Ce valence states
of Pt1/CeO2, 2.5 nm Pt/CeO2 and 7.0 nm Pt/CeO2 are further
confirmed by XPS analysis (Figure S9). Importantly, for the Pt
4f XPS spectra, the binding energies of Pt 4f2/7 and 4f2/5 in
Pt1/CeO2 are close to Pt2+ species, indicating that Pt single-
site supported on CeO2 are oxidized owing to the electron
transfer Pt to CeO2.[26] Interestingly, the Pt species of 2.5 nm
Pt/CeO2 and 7.0 nm Pt/CeO2 are mainly metallic Pt. The
previous reports have certified that the Pt-CO bonding energy
of CO absorption on positive Pt species is lower than on
metallic Pt.[19,27] Thus, for the methanol dehydrogenation
process, as the COads species forms, it is much easier to desorb
CO from positive Pt sites in Pt1/CeO2 than the metallic Pt sites
of other two catalysts (Figure S10). Therefore, the size effect
and valence states of Pt may explain the relative catalytic
activity of these catalyst samples, with activity ordered as:
single-site Pt1/CeO2 >> 2.5 nm Pt/CeO2 > 7.0 nm Pt/CeO2.
The single-site Pt1/CeO2 also performed excellent catalytic
activity in hydrogen production from other alcohols, namely
ethanol, 1-propanol, isopropanol, 1-buthanol, and benzyl
alcohol (Figure 4). The proposed mechanism of the alcohol
dehydrogenation process includes several steps. First, the
alcohol molecules absorb on Pt sites and form R1R2CHOads by
breaking O-H bond, then dehydrogenation into R1R2COads. As
for methanol, after formaldehyde (CH2O) intermediate is
formed, it will further dehydrogenate to yield formyl (CHO)
and carbon monoxide (CO).[10,24,25] Hence, compared to other
alcohols, all the hydrogen in methanol can be released to
generate two molecules of H2 and leave CO behand. For other
longer chain alcohols, after aldehydes or ketones formed,
more energy is needed for additional dehydrogenation steps.
Moreover, for primary alcohols, the activity of substrates is
decreased with the growth of carbon chain, and after
transformation to corresponding aldehydes, some C-C bonds
will be cleaved to form CO and alkanes. Besides, the hydrogen
Figure 3. (a) Turnover frequency (TOF) of hydrogen
production from methanol in terms of methanol conversion
per Pt site of Pt1/CeO2, 2.5 nm Pt/CeO2 and 7.0 nm Pt/CeO2,
at different temperatures. (b) the stability Pt1/CeO2, 2.5 nm
Pt/CeO2 and 7.0 nm Pt/CeO2 at reaction condition at 300 oC.
The dehydrogenation mechanism of methanol on the Pt
surface have been experimentally examined using advanced
techniques such as: TPD, EELS, IR, UPS, and AES. The
dehydrogenation mechanism has also been examined via DFT
theoretical simulation.[10,23-25] These results indicate that, at
low temperature, methanol molecularly absorbs at the surface
of Pt and then decomposes to form methoxy species by
breaking the O-H bond. Then successively, the three C-H
bonds will be broken up and generate the final products COads
and Hads. Importantly, both experimental and computational
results demonstrated that smaller Pt nanoparticle size favor
the methanol dehydrogenation due to the energy barriers of
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Page 4 of 6
production from benzyl alcohol and isopropanol is higher,
owing to their first dehydrogenated products are more stable.
Notes
1
The authors declare no competing financial interests.
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ACKNOWLEDGMENT
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This work was supported by the Hydrogen Materials
Advanced Research Consortium (HyMARC), established as
part of the Energy Materials Network by the U.S. Department
of Energy, Office of Energy Efficiency and Renewable Energy,
Fuel Cell Technologies Office, under Contract Number DE-
AC02-05CH11231. This research used resources of the
Advanced Light Source, which is a DOE Office of Science User
Facility under contract no. DE-AC02-05CH11231. L. Chen, Y.
Liu, J. Guo, D. Prendergast and J. Su were supported by a User
Project at The Molecular Foundry at Lawrence Berkeley
National Laboratory, which is supported by the Office of
Science of the U.S. Department of Energy under contract no.
DE-AC02-05CH11231. Sandia National Laboratories is a multi-
mission laboratory managed and operated by National
Technology and Engineering Solutions of Sandia, LLC., a
wholly owned subsidiary of Honeywell International, Inc., for
the U.S. Department of Energy’s National Nuclear Security
Administration under Contract No. DE-NA-0003525. L. Chen
and S. Wang thank the China Scholarship Council (CSC) for
financial support.
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REFERENCES
(1) Schultz, M. G.; Diehl, T.; Brasseur, G. P.; Zittel, W. Air Pollution
and Climate-Forcing Impacts of a Global Hydrogen Economy. Science
2003, 302, 624.
(2) Steele, B. C. H.; Heinzel, A. Materials for fuel-cell technologies.
Nature 2001, 414, 345.
(3) Schneemann, A.; White, J. L.; Kang, SY.; Jeong, S.; Wan, L. F.;
Cho, E. S.; Heo, T. W.; Prendergast, D.; Urban, J. J.; Wood, B. C.;
Allendorf, M. D.; Stavila, V. Nanostructured metal hydrides for
hydrogen storage. Chem. Rev., 2018, 118, 10775.
(4) Allendorf, M.D.; Hulvey, Z.; Gennett, T.; Ahmed, A.; Autrey, T.;
Camp, J.; Cho, E. S.; Furukawa, H.; Haranczyk, M.; Head-Gordon, M.;
Jeong, S.; Karkamkar, A.; Liu, D.-J.; Long, J. R.; Meihaus, K. R.; Nayyar,
I. H.; Nazarov, R.; Siegel, D. J.; Stavila, V.; Urban, J. J Veccham S. P.;
Wood, B.C. An assessment of strategies for the development of solid-
state adsorbents for vehicular hydrogen storage. Energy Environ. Sci.,
2018, 11, 2784.
(5) Preuster, P.; Papp, C.; Wasserscheid, P. Liquid organic hydrogen
carriers (LOHCs): toward a hydrogen-free hydrogen economy. Acc.
Chem. Res. 2017, 50, 74.
(6) Markiewicz, M.; Zhang, Y. Q.; Bö smann, A.; Brü ckner, N.;
Thöming, J.; Wasserscheid, P.; Stolte, S. Environmental and health
impact assessment of Liquid Organic Hydrogen Carrier (LOHC)
systems–challenges and preliminary results. Energy Environ. Sci. 2015,
8, 1035.
Figure 4. (a) Turnover frequency (TOF) of hydrogen
production from different alcohol in terms of hydrogen
production per Pt site of Pt1/CeO2 at different temperature. (b)
Products diffusion of different alcohol at 300 C by Pt1/CeO2
catalyst.
o
In summary, a well-defined single-site Pt1/CeO2 catalyst was
developed and its catalytic performance was evaluated for
hydrogen generation from methanol. Importantly, compared
to the Pt/CeO2 nanoparticle catalysts (2.5 nm Pt/CeO2 and 7.0
Pt/CeO2), the single-site catalyst Pt1/CeO2, exhibited reaction
rates that are 40 and 800 times higher, respectively. Moreover,
beside the methanol, this single-site catalyst performed high
efficiency in other liquid alcohol hydrogen production.
Ultimately, this in-depth study highlights the benefits of
single-site catalyst and paves the way for further rational
design of highly efficient catalysts for hydrogen production.
ASSOCIATED CONTENT
Supporting Information
(7) Teichmann, D.; Arlt, W.; Wasserscheid, P.; Freymann, R. A
future energy supply based on Liquid Organic Hydrogen Carriers
(LOHC). Energy Environ. Sci. 2011, 4, 2767.
This material is available free of charge via the Internet at
http://pubs.acs.org.
Experimental details, characterization data and partial
catalytic data, including the synthesis of catalysts, the
characterization of CeO2 support and catalysts, the
characterization of catalyst after reaction, and the catalytic
result of some control tests.
(8) Palo, D. R.; Dagle, R. A.; Holladay, J. D. Methanol steam
reforming for hydrogen production. Chem. Rev. 2007, 107, 3992.
(9) Liu, W.-C.; Baek, J.; Somorjai, G. A. The Methanol Economy:
Methane and Carbon Dioxide Conversion. Top. Catal. 2018, 61, 530.
(10) Greely, J.; Mavrikakis, M. Competitive paths for methanol
decomposition on Pt (111). J. Am. Chem. Soc. 2004, 126, 3910.
(11) Kuhn, J. N.; Huang, W.; Tsung, C.-K.; Zhang, Y.; Somorjai, G. A.
Structure Sensitivity of Carbon−Nitrogen Ring Opening: Impact of
Platinum Particle Size from below
1 to 5 nm upon Pyrrole
AUTHOR INFORMATION
Hydrogenation Product Selectivity over Monodisperse Platinum
Nanoparticles Loaded onto Mesoporous Silica. J. Am. Chem. Soc.
2008, 130, 14026.
(12) Tsung, C. K.; Kuhn, J. N.; Huang, W. Y.; Aliaga, C.; Hung, L. I.;
Somorjai, G. A.; Yang, P. D. Sub-10 nm platinum nanocrystals with size
Corresponding Author
jisu@lbl.gov
somorjai@berkeley.edu
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Page 5 of 6
Journal of the American Chemical Society
and shape control: catalytic study for ethylene and pyrrole
hydrogenation. J. Am. Chem. Soc. 2009, 131, 5816.
(20) Rioux, R. M.; Song, H.; Hoefelmeyer, J. D.; Yang, P.; Somorjai,
G. A. High-surface-area catalyst design: synthesis, characterization,
and reaction studies of platinum nanoparticles in mesoporous SBA-15
silica. J. Phys. Chem. B 2005, 109, 2192.
(21) Aliaga, C.; Park, J. Y.; Yamada, Y.; Lee, H. S.; Tsung, C. K.; Yang,
P. D.; Somorjai, G. A. Sum frequency generation and catalytic reaction
studies of the removal of organic capping agents from Pt nanoparticles
by UV− ozone treatment. J. Phys. Chem. C 2009, 113, 6150.
(22) Kappers, M. J.; van der Maas, J. H. Correlation between CO
frequency and Pt coordination number. A DRIFT study on supported
Pt catalysts. Catal. Lett. 1991, 10, 365.
(23) Gibson, K. D.; Dubois, L. H. Step effects in the thermal
decomposition of methanol on Pt (111). Surf. Sci. 1990, 233, 59.
(24) Greeley, J.; Mavrikakis, M. A first-principles study of methanol
decomposition on Pt (111). J. Am. Chem. Soc. 2002, 124, 7193.
(25) Desai, S. K.; Neurock, M.; Kourtakis, K. A periodic density
functional theory study of the dehydrogenation of methanol over Pt
(111). J. Phys. Chem. B 2002, 106, 2559.
1
2
3
4
5
6
7
8
(13) Qiao, B.; Wang, A.; Yang, X.; Allard, L. F.; Jiang, Z.; Cui, Y.; Liu,
J.; Li, J.; Zhang, T. Single-atom catalysis of CO oxidation using
Pt1/FeOx. Nat. Chem. 2011, 3, 634.
(14) Lin, L.; Zhou, W.; Gao, R.; Yao, S.; Zhang, X.; Xu, W.; Zheng, S.;
Jiang, Z.; Yu, Q.; Li, Y. W.; Shi, C.; Wen, X. D.; Ma, D. Low-temperature
hydrogen production from water and methanol using Pt/α-MoC
catalysts. Nature 2017, 544, 80.
(15) Liu, P.; Zhao, Y.; Qin, R.; Mo, S.; Chen, G.; Gu, L.; Chevrier, D.
M.; Zhang, P.; Guo, Q.; Zang, D.; Wu, B.; Fu, G.; Zheng, N.
Photochemical route for synthesizing atomically dispersed palladium
catalysts. Science 2016, 352, 797.
(16) Yang, X. F.; Wang, A. Q.; Qiao, B. T.; Li, J.; Liu, J. Y.; Zhang, T.
Single-atom catalysts: a new frontier in heterogeneous catalysis. Acc.
Chem. Res. 2013, 46, 1740.
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(17) Chen, Y.; Ji, S.; Chen, C.; Peng, Q.; Wang, D.; Li, Y. Single-atom
catalysts: synthetic strategies and electrochemical applications. Joule
2018, 2, 1242.
(26) Wiebenga, M. H.; Kim, C. H.; Schmieg, S. J.; Oh, S. H.; Brown,
D. B.; Kim, D. H.; Lee, J. H.; Peden, C. H. F. Deactivation mechanisms
of Pt/Pd-based diesel oxidation catalysts. Catal. Today 2012, 184, 197.
(27) Mao, M.; Lv, H.; Li, Y.; Yang, Y.; Zeng, M.; Li, N.; Zhao, X. Metal
Support Interaction in Pt Nanoparticles Partially Confined in the
Mesopores of Microsized Mesoporous CeO2 for Highly Efficient
Purification of Volatile Organic Compounds. ACS Catal. 2016, 6, 418.
(18) Nie, L.; Mei, D.; Xiong, H.; Peng, B.; Ren, Z.; Hernandez, X.;
DeLaRiva, A.; Wang, M.; Engelhard, M. H.; Kovarik, L.; Datye, A. K.;
Wang, Y. Activation of surface lattice oxygen in single-atom Pt/CeO2
for low-temperature CO oxidation. Science 2017, 358, 1419.
(19) Chen, J.; Wanyan, Y.; Zeng, J.; Fang, H.; Li, Z.; Dong, Y.; Qin, R.;
Wu, C.; Liu, D.; Wang, M.; Kuang, Q.; Xie, Z.; Zheng, L. Surface
Engineering Protocol To Obtain an Atomically Dispersed Pt/CeO2
Catalyst with High Activity and Stability for CO Oxidation. ACS
Sustainable Chem. Eng. 2018, 6, 14054.
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