Supporting Information for
From Rice Bran to High Energy Density Supercapacitors: A
New Route to Control Porous Structure of 3D Carbon
Jianhua Hou, a Chuanbao Cao, a* Xilan Ma, a Faryal Idrees, a Bin Xu, b Xin Hao b
and Wei Linb
a
Center of Materials Science, Beijing Institute of Technology, Beijing 100081, P. R.
China
b
State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of
Electrochemical Process and Technology for Materials, Beijing University of
Chemical Technology, Beijing 100029, P. R. China.
Corresponding Author: E-mail address: cbcao@bit.edu.cn
Tel: +86 10 6891 3792; Fax: +86 10 6891 3792;
Figure S1. The typical of RBC-X electrode’s Radius and height (Formula s1 is used
to calculate density of RBC-X electrode).
ρ
m
m
m


2
v
s  h πr  h
(S1)
By using S1 formula density of electrode material calculated are: 0.45 g cm-3 for
RBC-4, 0.46 g cm-3 for RBC-3, 0.56 g cm-3 for RBC-2 and 0.79 g cm-3 for RBC-1.
Table S1.
Combustion elemental analysis and XPS result for the RB and RBCs.
Elemental analysis (wt.%)
Sample
C
N
H
S
RB
39.72
6.64
2.13
RBC
77.81
4.65
RBC-1
84.32
RBC-2
XPS (wt.%)
C
O
N
Cl
0.43
45.34
47.92
6.74
0.00
1.68
0.34
82.28
12.77
4.83
0.12
1.99
1.53
0.36
88.15
10.28
1.57
0.00
87.45
1.03
1.27
0.28
90.07
8.77
1.12
0.04
RBC-3
91.67
0.74
1.06
0.15
92.56
6.55
0.78
0.11
RBC-4
92.57
0.41
1.02
0.21
95.12
4.33
0.52
0.03
YP-17D
92.43
0.15
1.43
0.00
-
-
-
-
C
60000
50000
40000
30000
intensity (a.u.)
70000
N
O
RBC
RBC-1
RBC-2
RBC-3
RBC-4
20000
10000
0
0
200
400
600
800
Binding energy (eV)
Binding energy (eV)
Figure S2. XPS survey spectrum of the RBCs.
1000
a
-1
b
1.0
IR
RBC-4
RBC-3
RBC-2
RBC-1
200
Voltage (V)
Specific Capacitance(F g )
300
100
0
10 mV s
-1
-100
-200
0.0
0.2
0.4
0.6
Voltage (V)
0.8
0.6
0.4
0.2
RBC-3
RBC-1
RBC-4
RBC-2
-300
0.8
0.0
1.0
0
50
100
150
Time (s)
200
250
Figure S3. Electrochemical performance characteristics of RBC-X measured in a
two-electrode system in the 6 M KOH electrolyte. (a) CV curves at the scan rate of
10 mV s−1; (b) Galvanostatic charge–discharge curves at current density of 1 A g−1
b
a
-1
2Ag
-1
5Ag
-1
10Ag
-1
20Ag
-1
30Ag
-1
40Ag
-1
50Ag
1.0
200
-1
5mVs
-1
20mVs
-1
50mVs
-1
200mVs
-1
500mVs
100
0
-100
Potential(V)
-1
Specific Capacitance(Fg )
300
-200
0.8
0.6
0.4
0.2
-300
0.0
0.2
0.4
0.6
Potential(V)
0.8
1.0
0.0
0
20
40
60
80
Time (s)
100
120
140
Figure S4. (a) Cyclic voltammograms of RBC-4 at various scan rates; (b)
Galvanostatic charge–discharge curves of RBC-4 at different current densities.
60
15
40
-z"(ohm)
-z"(ohm)
50
30
5
20
10
0
0
10
0
10
0
20
5
10
z'(ohm)
30
40
z'(ohm)
50
15
60
Figure S5. Nyquist plots and its expanded high frequency region (inset).
Table S2 Comparison of specific capacitance for the obtained activated carbon
sample with those of previously reported samples.
Precursor
rice husk
SBET
(m2 g-1)
1565
sunflower
seed shell
2509
animal bone
2157
glucose
bacillus
subtilis
2096
1578
Capacitance
(F g-1)
245a
0.05 A g-1
233a
2 A g-1
311 a
0.25 A g-1
a
microporous
carbon
nanosheets
mesoporous
carbon thin
films
EM-CCG
film
Carbon
nanocages
silk
rice bran
2264
791
690
557167c
1854
2557
2475
-1
144
185a
10 A g
0.05 A g-1
143a
10 A g-1
221a
2 mV s-1
141a
200 mV s-1
310b
0.2 A g-1
200b
10A g-1
190a
Ph-POSS
Current
density
Electrolyte
Ref.
6 M KOH
S1
30.%
KOH
S2
7 M KOH
S3
1 M H2SO4
S4
6 M KOH
S5
6 M KOH
S6
0.02 A g-1
110a
2 A g-1
213b
0.5 A g-1
160b
10 Ag-1
136b
0.5 A g-1
85b
5 A g-1
192a
0.1 A g-1
171a
1 A g-1
146a
10 A g-1
260a
0.1 A g-1
178a
10 A g-1
112a
100 A g-1
264a
0.1 A g-1
162 a
6.2 A g-1
120 a
52.5 A g-1
323a
0.1 A g-1
265a
10 A g-1
182a
100 A g-1
6 M KOH
S7
6 M KOH
S8
1 M H2SO4
S9
1 M H2SO4
S10
2 M H2SO4
S11
6 M KOH
This
work
a
A two-electrode system was used.
b
A three-electrode system was used.
c
The SSA values obtained from the methylene blue (MB) adsorption are only valid
for macro- and mesoporous materials9.
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