· web viewxrd analysis. crystal sizes of s-graphene/pypbi/au calculated by scherrer’s equation...
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Supplementary Information
Growth and Deposition of Au Nanoclusters on Polymer-wrapped Graphene and Their Oxygen Reduction Activity
Tsuyohiko Fujigaya*1,2, ChaeRin Kim1, Yuki Hamasaki2, , and Naotoshi Nakashima*1,2,3
1International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan
2 Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka Nishi-ku, Fukuoka 819-0395, Japan E-mail: [email protected], [email protected]
3 JST-CREST, 5 Sanbancho, Chiyoda-ku, Tokyo, 102-0075, Japan
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Table S1 | XRD analysis. Crystal sizes of s-Graphene/PyPBI/Au calculated by Scherrer’s equation using the XRD patterns.
s-Graphene/PyPBI/Aux
FCC Assignment
X= 1.6 X= 3.3 X= 4.5
(111) 4.4 6.1 11.2
(200) 4.3 3.8 6.4
(220) 3.1 4.6 7.4
(311) 4.7 5.5 8.1
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Table S2 | XPS analysis. Au composition ratio of s-Graphene/PyPBI/Au determined from XPS narrow scans shown in Figure 7b.
Au(0) Au(I) Au(III)
s-Graphene/PyPBI/Au1.6 67.28 20.75 11.97
s-Graphene/PyPBI/Au3.3 75.74 16.99 7.27
s-Graphene/PyPBI/Au4.5 81.89 11.10 7.01
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Table S3 | Electrochemical analysis. Calculated number of electrons (n) transferred during ORR for the Au-NP.
s-Graphene/PyPBI/AuxX= 6. 6 3.3 1.6
number of electrontransfer (n) 1.7 2.4 2.3
a b c
Figure S1 | Low magnification TEM images. Low magnification of TEM images for
(a) s-Graphene/PyPBI/Au4.5, (b) s-Graphene/PyPBI/Au3.3 and (c)
s-Graphene/PyPBI/Au1.6.
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a b c
1.00 μm 1.00 μm1.00 μm
500 nm500 nm500 nm
Figure S2 | Comparison of the electron microscope images. STEM (a) bright-field
and (b) dark-field images and (c) SEM image of s-Graphene/PyPBI/Au3.3 at (upper)
lower and (lower) high magnifications.
a b
Figure S3 | Effect of PyPBI layer. (a, b) STEM images of Au-NPs directly grown on
s-Graphene using 0.14 mM of HAuCl4.
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a b
-3
-2
-1
0
-0.8 -0.6 -0.4 -0.2 0 0.2
400 rpm600 rpm800 rpm1200 rpm1600 rpm2400 rpm
Potential / V vs. Ag/AgCl
Cur
rent
den
sity
/ m
A c
m-2
-3
-2
-1
0
-0.8 -0.6 -0.4 -0.2 0 0.2
400 rpm600 rpm800 rpm1200 rpm1600 rpm2400 rpm
Potential / V vs. Ag/AgCl
Cur
rent
den
sity
/ m
A c
m-2
Figure S3 | Electrochemical analysis. LSV curves of (a) s-Graphene/PyPBI/Au4.5
and (b) s-Graphene/PyPBI/Au3.3 on the ORR at the specified rotation rates.
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