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Volume 4
Nano Research & Applications
ISSN: 2471-9838
Page 40
Notes:
August 16-18, 2018 | Dublin, Ireland
&
JOINT EVENT
12
th
Edition of International Conference on
Nanopharmaceutics and Advanced Drug Delivery
25
th
Nano Congress for Future Advancements
Nano Congress 2018
&
Nano Drug Delivery 2018
August 16-18, 2018
Thermally reduced gold nanoparticles confined by ordered mesoporous carbon as an efficient
catalyst for selective hydrogenation
G
old nanocatalysts represent a new generation of catalysts for the selective oxidation and reduction using molecular O
2
and H
2
, showing great potentials for green chemistry. Activated carbons are one of the most frequently used supports
in industry. However, activated carbon has been seldom used for gold deposition. Here a coordination-assisted self-assembly
approach is adopted for the intercalation of thermally reduced gold nanoparticles inside ordered mesoporous carbon
frameworks. An almost complete conversion of benzyl alcohol to benzoic acid is achieved within 60 min over the Au/C catalyst
with gold nanoparticles approximately 9.0 nm under 90ºC and 1 MPa, using potassium hydroxide as a base. A reduction of
gold particle size from 9.0 to 3.4 nm in the catalyst leads to a high activity toward the selective oxidation of benzyl alcohol
to benzyl acid and toward the reduction of p-nitrophenol to p-aminophenol at low temperatures such as 0°C. The electronic
modification of the d-orbitals of small particles is extremely important for chemisorption of O
2
at atmosphere pressure and
low temperatures. Interstingly, thermally reduced Au/C nanocatalyst with gold nanoparticles approximately 2.8 nm is highly
active and selective to convert p-chloronitrobenzene and 4-nitrophenol to corresponding amines using H
2
as a reducing agent,
reaching an initial reaction rate of 12.7 and 6.5 min
-1
, respectively. By comparison, the commercial Au/C catalyst is inert under
the same reaction conditions. Trapping by the SH-functionalized SBA-15 solids confirms the negligible gold leaching and the
heterogeneous active centers for thermally reduced Au/C. Obvious changes are undetected for catalytic performance after five
runs. These results indicate that the gold-containing mesoporous carbon catalyst is stable and can be reused. The simultaneous
thermal reduction of gold nanoparticles and pyrolysis of the matrix may facilitate the involvement of gold inside the carbon
matrix, the modification of carbon atoms on the gold surface, and the reconstruction of the surface induced by CO adsorption.
The generation of low-coordinated gold atoms possibly reduces the H
2
dissociation barrier, and can therefore significantly
improve the hydrogenation activity.
Biography
Ying Wan received her PhD degree in Industrial Catalysis from the East China University of Science and Technology in 2002. Then, she joined Shanghai Normal University
where she was promoted to a full professor in 2006. In 2005-2007, she carried out her postdoctoral research at Fudan University working with Professor Dongyuan Zhao.
Currently, Ying Wan is the leader of the Program for Innovative Research Team in University, China. Her research focuses on sintering-, and poisoning-resistance metal
nanocatalysts supported on mesoporous carbons, and their applications in green organic synthesis and energy chemistry. She has contributed to about 70 peer-reviewed
scientific publications with more than 7000-times citations and 3 books. She has been an associate editor of
Journal of Porous Materials
since 2013.
[email protected]Ying Wan
Shanghai Normal University, China
Ying Wan, Nano Res Appl 2018, Volume 4
DOI: 10.21767/2471-9838-C3-014