Journal of the American Chemical Society
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hours in to the reaction. All reactions were stopped at 3
ASSOCIATED CONTENT
Supporting information
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hours. The products were harvested through centrifuge. No
extra washing steps were carried out to preserve the
products as much as possible. Then, the collected materials
were dispersed in toluene and vacuum filtered on to a
nitrocelloluse membrane. The copper products on filter
membrane were dried in vacuum oven and weighed for
yield calculation.
Experimental details, additional TEM images, EPR spectra.
This material is available free of charge via the Internet at
AUTHOR INFORMATION
Corresponding Author
Funding Sources
Characterizations of metal NWs
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The morphology of synthesized product was examined
using transmission electron microscope (TEM) and
scanning electron microscope (SEM, JOEL JSM ꢀ 6340F).
Lowerꢀresolution TEM images were acquired using Hitachi
H7650, operated at 100 kV, and higherꢀresolution TEM
characterizations were carried out on FEI Tecnai G20, with
high voltage set at 200 kV. Xꢀray diffraction (XRD) was
acquired using a Bruker Dꢀ8 General Area Detector
Diffraction System (GADDS) with HIꢀSTAR area chargeꢀ
coupled device (CCD) detector, equipped with a CoꢀKα
source (λ = 1.789ꢃÅ).
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This work was financially supported by BASF Corporation
(Funding No. 84428967).
ACKNOWLEDGMENT
The authors gratefully thank Dr. B. Wu and Prof. G.
Stucky for the facility support at UC Santa Barbara, Dr. R.
Larson for the help in the benzoin derivative syntheses,
Prof. K. Lakshmi for helpful discussion in EPR measureꢀ
ments and Ms. C. Xie for proof reading. We also thank Dr.
S. Walker for the help with the in-situ EPR studies at the
Materials Research Laboratory, UC Santa Barbara. The
MRL Shared Experimental Facilities are supported by the
MRSEC Program of the NSF under Award No. DMR
1121053; a member of the NSFꢀfunded Materials Research
Facilities. Work at the NCEM, Molecular Foundry was
supported by the Office of Science, Office of Basic Energy
Sciences, of the U.S. Department of Energy under Contract
No. DEꢀAC02ꢀ05CH11231.
In-situ electron paramagnetic resonance (EPR)
measurement
EPR sample was prepared in airꢀtight EPR tubes (4 mm
LPV 250mm EPR sample tube) purchased from Wilmad
LabGlass. All sample tubes were cleaned with acetone and
isopropanol under ultrasonication and then dried in heated
oven before use.
Before loading sample in EPR tubes, benzoin and CuCl2
solution was prepared freshly right before the
measurement. Benzoin were dispersed in oleylamine under
vigorous stirring with concentration of 0.8mmol/g. CuCl2
oleylamine solution with concentration of 0.02mmol/g was
prepared. In a standard reaction sample preparation, 75ꢁL
0.8mmol/g benzoin oleylamine mixture was added to the
EPR tube with gentle shaking. Then 75ꢁL of CuCl2
solution was added on top of the mixture in the tube. The
tube was shaken back and forth until the solution was well
mixed and settled to the bottom. The loaded EPR tube was
connected to a Schlenk line then degassed and purged with
Argon for 5 cycles and finally, sealed with slight vacuum
before going through the measurement.
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