RSC Advances
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COMMUNICATION
DOI: 10.1039/C5RA01649E
ethanol and water. Then np-Ag was reused without further
purification. From scheme 2, it can be seen that the catalyst could be
reused even seven times without reducing the catalytic activity.
Fig.1b is the SEM image of the recovered catalyst after seven uses.
Compared to the fresh one (Fig. 1a), little change in porous
morphology and feature dimension was observed, but the ligament
size coarsened from 30 nm before the reaction to around 40 nm.
After the reaction the XPS spectrum of np-Ag was also detected, Fig.
2b. The binding energies of Ag 3d5/2 and Ag 3d3/2 were appeared at
368.5 and 374.5 eV, which implied that the surface status did not
change after the reaction. To clarify whether the np-Ag catalyst had
been leached into the reaction mixture or not, the reaction solution
was also tested by inductivity coupled plasma (ICP-AES) analysis
when the conversion of 4-NP was about 50%. The rate was lower
than the detection limits (<0.02 ppm). No leaching of silver was
detected. These evidences proved that np-Ag was a green and
sustainable catalyst for the reduction of aromatic nitro compounds.
Electronic Supplementary Information (ESI) available: [details of any
supplementary information available should be included here]. See
DOI: 10.1039/c000000x/
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Financial support from the National Science Foundation of China
(21472117 and 21176144) was acknowledged.
Notes and references
a
School of Chemistry and Chemical Engineering, Shandong University,
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1092.
†
Footnotes should appear here. These might include comments
27 S. Saha, A. Pal, S. Kundu, S. Basu, T. Pal, Langmuir 2010, 26, 2885-
relevant to but not central to the matter under discussion, limited
experimental and spectral data, and crystallographic data.
2893.
4 | J. Name., 2012, 00, 1-3
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