ACS Catalysis
Research Article
particle size), aluminum oxide nanopowder (<50 nm (BET)),
and all nitro and/or nitrile compounds used in the tandem
reaction were purchased from Sigma-Aldrich and used as
received. Nickel(II) acetate tetrahydrate (98%) was obtained
from Strem Chemicals.
with D2O, DMSO, CD3OD, or CDCl3 as the solvent
depending on the product separated.
ASSOCIATED CONTENT
* Supporting Information
■
S
Characterization Methods. Samples for transmission
electron microscopy (TEM) analysis were prepared by
depositing a single drop of the diluted NP dispersion in
hexane amorphous carbon-coated copper grids. Images were
obtained on a Philips CM20 at 200 kV. High resolution TEM
(HRTEM) images were obtained on a JEOL 2100F with an
accelerating voltage of 200 kV. X-ray diffraction (XRD)
patterns were collected on a Bruker AXS D8-advanced
diffractometer with Cu Kα radiation (λ = 1.5418 Å).
Inductively coupled plasma (ICP) elemental analysis measure-
ments were carried out on a JY2000 Ultrace ICP atomic
emission spectrometer equipped with a JY AS 421 autosampler
and 2400g/mm holographic grating. For ICP analysis, an
aliquot of the NPs in hexane was dried and subsequently
dissolved in warm (∼75 °C) aqua regia for 30 min to ensure
complete dissolution of metal into the acid. The solution was
then diluted with 2% HNO3 solution for analysis. 1H NMR and
13C NMR spectra were recorded on a Bruker Avance DPX 400
MHz spectrometer.
Synthesis of NiPd Alloy NPs. In a typical synthesis of
Ni30Pd70 NPs, 0.2 mmol of palladium(II) acetylacetonate
(Pd(acac)2) and 0.2 mmol of nickel(II) acetate tetrahydrate
(Ni(ac)2·4H2O) were dissolved in 3 mL of OAm. The
precursor mixture was quickly injected into a mixture of 200
mg of BBA, 3 mL of OAm, and 7 mL of 1-octadecene (ODE)
at 100 °C under magnetic stirring in an argon environment.
The reaction was allowed to proceed for 1 h and cooled to
room temperature. Then acetone/ethanol (v/v = 7/3) was
added, and the NP product was separated by centrifugation at
9000 rpm for 10 min. The NPs were redispersed in hexane and
then stored for further use.
TEM images of C-NiPd and Al2O3−NiPd catalysts, NMR
spectra of amine compounds, and previous hydrogenation
reactions. This material is available free of charge via the
AUTHOR INFORMATION
■
Corresponding Authors
Author Contributions
∥H.G. and S.F.H. contributed equally to this work.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work was supported by the Scientific and Technological
Research Council of Turkey (TUBITAK, Project No:
113Z276), the U.S. Army Research Laboratory, and the U.S.
Army Research Office under the Multi University Research
Initiative (MURI, grant number W911NF-11-1-0353) on
“Stress-Controlled Catalysis via Engineered Nanostructures.”
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reduced compounds were determined by H and 13C NMR
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dx.doi.org/10.1021/cs500167k | ACS Catal. 2014, 4, 1777−1782