Au/N-TiO2

N-TiO2
TiO2

Intensity (a.u.)
TNT
P25


☆

☆

☆


20

30




40
50


60


70

80
2(°)
Figure S1. XRD patterns of P25, TNT, TiO2, N-TiO2 and Au/N-TiO2. Asterisk, rhombus, and open
star denote rutile, anatase, and Au, respectively.
(a)
(b)
Au (111)
d = 0.239 nm
Au
TiO2 (101)
d = 0.360 nm
(101)
(004)
(200)
5 0
2 nm
n m
N
(c)
Ti
Au
Au
Au
O
Au
Au
0
2
Ti
4
Au
6
8
Au
10
12
14
16
Energy (keV)
Figure S2. (a) TEM image of as synthesized Au/N-TiO2, inset in the lower right corner is the
SAED pattern of anatase TiO2 and (b) HRTEM image and (c) EDX spectrum of Au/N-TiO2.
250000
(a)
O 1s
200000
Ti 2p
Counts
150000
Ti 2s
100000
50000
C 1s
Au 4f
N 1s
0
1000
800
600
400
200
0
Binding energy/eV
60000
(b) O 1s
529.6
50000
Counts
40000
30000
20000
531.3
532.1
10000
0
534
532
530
Binding energy/eV
528
526
(c) N 1s
2200
399.7
Counts
2100
2000
1900
1800
1700
412
410
408
406
404
402
400
398
396
394
392
Binding Energy/ev
4000
(d) Au 4f
82.8
3500
3000
86.5
Counts
2500
2000
1500
1000
500
0
-500
90
88
86
84
82
Binding energy/eV
Figure S3. XPS spectra of (a) Au/N-TiO2 and core level spectra of (b) O 1s, (c) N 1s, and (d) Au
4f.
Absorbance (a.u.)
Au/N-TiO2
Au/TiO2
N-TiO2
TiO2
300
350
400
450
500
550
600
650
700
Wavelength (nm)
Figure S4. UV–vis diffuse reflectance spectra of TiO2, Au/TiO2, N-TiO2, and Au/N-TiO2.
10000
N-TiO2
TiO2
Intensity (a.u.)
8000
Au/N-TiO2
Au/TiO2
6000
4000
2000
0
300
350
400
450
500
550
600
Wavelength (nm)
Figure S5. PL emission spectra of TiO2, Au/TiO2, N-TiO2, and Au/N-TiO2 under the irradiation of
254 nm.
250
Amount of hydrogen evolution (mol)
(a) UV
200
150
-1
Rate (mol h )
Samples
100
50
TiO2
1.75
N-TiO2
0.69
Au/TiO2
29.00
Au/N-TiO2
26.17
0
0
1
2
3
4
5
6
7
8
9
Time (h)
3500
Amount of hydrogen evolution (mol)
(b) UV-vis
3000
2500
2000
1500
-1
Rate (mol h )
7.65
Samples
TiO2
1000
N-TiO2
500
21.56
Au/TiO2
321.35
Au/N-TiO2
412.60
0
0
1
2
3
4
5
6
7
8
9
Time (h)
Figure S6. Photocatalytic activity for water splitting under the irradiation of (a) UV and (b)
UV–vis light.
Amount of hydrogen evolution (mol)
60
Ar
(a)
Ar
50
40
Ar
30
20
10
0
Amount of hydrogen evolution (mol)
0
4
8
16
20
24
28
32
28
32
Ar
(b)
3000
12
Ar
2500
Ar
2000
1500
1000
500
0
0
4
8
12
16
20
24
Time (h)
Figure S7. The repeated hydrogen evolution tests over Au/N-TiO2 under UV-vis light in (a) pure
water and (b) methanol/water solution with purging of Ar in every 8 h.
0.10
(a) UV
TiO2
0.08
Au/TiO2
Current /A
0.06
Au/N-TiO2
N-TiO2
0.04
0.02
0.00
-0.02
ON
OFF
-0.04
0
5
10
15
20
25
30
35
40
45
50
55
60
Time /s
0.20
(b) Vis
Au/N-TiO2
0.15
N-TiO2
Current /A
Au/TiO2
TiO2
0.10
0.05
0.00
ON
OFF
-0.05
0
10
20
30
40
50
60
Time /s
Figure S8. Photocurrents of TiO2, N-TiO2, Au/TiO2, and Au/N-TiO2 electrodes at zero bias
voltage irradiated with (a) UV (λ = 254 nm) and (b) visible light (λ > 400 nm) for 20 s.
400
Au/N-TiO2 - dark
350
Au/N-TiO2 - vis
CPE
-Z"/ohm
300
Rs
250
w
Rct Ws
200
1
150
Parameters
Rct (Ω cm-2)
Rs (Ω cm-2)
100
CPE×108 (F cm−2)
Y0 ×104 (Ω-1 cm-2 S0.5)
50
Dark
185
24.5
Vis
146
19.5
1.61
1.95
5.64
6.76
2
0
0
100
200
300
400
500
600
Z'/ohm
Figure S9. EIS Nyquist plots for Au/N-TiO2 in dark and under the irradiation of visible light. Inset
is the suggested equivalent circuit and the fitting results for Au/N-TiO2. Rs and Rct are the
electrolyte and electron-transfer resistance, respectively. CPE is the constant phase element, which
also represents the double layer capacitance. Ws is the Warburg impedance. Y0 is the value of
admittance and expresses a reciprocal relationship to the Warburg coefficient, which is able to
predict the Warburg impedance and diffusion coefficient.
Figure S10. Schematic illustration of Au/N-TiO2 for water splitting under the irradiation of (a) UV
and (b) visible light. Pathway I denotes the generation of charge carriers in TiO2. Pathway II
represents the reversible electron transfer between charged diamagnetic Nb- and neutral
paramagnetic Nb•, and the excitation of electrons into the conduction band. Pathway III shows the
acceleration of photo-induced electrons transfer by Au loading. Pathway IV denotes the SPR
effect of loaded Au nanoparticles.
Supporting Information Legends
Figure S1. XRD patterns of P25, TNT, TiO2, N-TiO2 and Au/N-TiO2. Asterisk,
rhombus, and open star denote rutile, anatase, and Au, respectively.
Figure S2. (a) TEM image of as synthesized Au/N-TiO2, inset in the lower right
corner is the SAED pattern of anatase TiO2 and (b) HRTEM image and (c) EDX
spectrum of Au/N-TiO2.
Figure S3. XPS spectra of (a) Au/N-TiO2 and core level spectra of (b) O 1s, (c) N 1s,
and (d) Au 4f.
Figure S4. UV–vis diffuse reflectance spectra of TiO2, Au/TiO2, N-TiO2, and
Au/N-TiO2.
Figure S5. PL emission spectra of TiO2, Au/TiO2, N-TiO2, and Au/N-TiO2 under the
irradiation of 254 nm.
Figure S6. Photocatalytic activity for water splitting under the irradiation of (a) UV
and (b) UV–vis light.
Figure S7. The repeated hydrogen evolution tests over Au/N-TiO2 under UV-vis light
in (a) pure water and (b) methanol/water solution with purging of Ar in every 8 h.
Figure S8. Photocurrents of TiO2, N-TiO2, Au/TiO2, and Au/N-TiO2 electrodes at zero
bias voltage irradiated with (a) UV (λ = 254 nm) and (b) visible light (λ > 400 nm) for
20 s.
Figure S9. EIS Nyquist plots for Au/N-TiO2 in dark and under the irradiation of
visible light. Inset is the suggested equivalent circuit and the fitting results for
Au/N-TiO2. Rs and Rct are the electrolyte and electron-transfer resistance,
respectively. CPE is the constant phase element, which also represents the double
layer capacitance. Ws is the Warburg impedance. Y0 is the value of admittance and
expresses a reciprocal relationship to the Warburg coefficient, which is able to predict
the Warburg impedance and diffusion coefficient.
Figure S10. Schematic illustration of Au/N-TiO2 for water splitting under the
irradiation of (a) UV and (b) visible light. Pathway I denotes the generation of charge
carriers in TiO2. Pathway II represents the reversible electron transfer between
charged diamagnetic Nb- and neutral paramagnetic Nb•, and the excitation of electrons
into the conduction band. Pathway III shows the acceleration of photo-induced
electrons transfer by Au loading. Pathway IV denotes the SPR effect of loaded Au
nanoparticles.