Supporting information: photocatalytic hydrogen evolution ...Supporting information: TiO2-supported...
Transcript of Supporting information: photocatalytic hydrogen evolution ...Supporting information: TiO2-supported...
Supporting information:
TiO2-supported Pt single atoms by surface organometallic chemistry for photocatalytic hydrogen evolution
Gabriel Jeantelot,a Muhammad Qureshi,a Moussab Harb,*a Samy Ould-Chikh,a Dalaver H. Anjum,b Edy Abou-Hamad,b Antonio Aguilar-Tapia,c Jean-Louis Hazemann,c Kazuhiro Takanabe,a Jean-Marie Basset*a
a. Kaust Catalysis Center (KCC), Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabiab. Core Labs, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabiac. Institut Néel, UPR2940 CNRS, University of Grenoble Alpes, F-38000 Grenoble (France)
Supplementary figures:
Fig. S1 Setup used for grafting reactions
Electronic Supplementary Material (ESI) for Physical Chemistry Chemical Physics.This journal is © the Owner Societies 2019
Vacuum pump
GC
argon
circulation pum
p
vacuum gauge
Cold trap
Photoreactor
Xe lamp
Stirplate
Fig. S2 Photocatalysis setup
1550 1500 1450 1400 1350 1300 1250
131213411428
1477
b) 5% PtGR:TiO2
a) 0.5% PtGR:TiO2
1342
1313
1431
c) Me2Pt(COD) (on KBr)
Abs
orba
nce
(A.U
)
Wavenumber (cm-1)
1479
1520
1452
1448
Fig. S3 Infrared spectroscopy (DRIFTS) of a) 0.5%PtGR:TiO2 ; b) 5% PtGR:TiO2 ; c) Me2Pt(COD) on KBr.
Material Band positionsPtGR:TiO2
(this work)1479 1452 1431 1342 1313
Me2Pt(COD) (this work)
1477 1448 1428 1341 1313
Cl2Pt(COD) 14791, 14762 1446,3 14512 14321, 14273, 14262
13391,3, 13402 13101, 13123
1,5-cyclooctadiene 14874,5, 14833 14485, 14474, 14433
14265, 14254, 14233
13575, 13564, 13523
13205, 13214
Table S1 Comparative table of the infrared absorption bands of the grafted materials, Pt(COD) complexes (Me2Pt(COD) ; Cl2Pt(COD)) and “free” 1,5-cyclooctadiene.
200 180 160 140 120 100 80 60 40 20 0
Cyclooctadiene adsorbed on {001}-anatase
28 ppm
46 ppm
Inte
nsity
(A.U
.)
Shift (ppm)
Fig. S4 13C MAS SSNMR spectrum of cyclooctadiene adsorbed on {001}-anatase
11550 11555 11560 11565 11570 11575 11580 115850123456789
101112
Pt powder (Pt0 ref)
(CH3)2Pt(COD) (Pt2+ ref)
0.5% PtGR:TiO2
Pt(acac)2 (Pt2+ ref)
Nor
mal
ized
abs
orba
nce
(AU
)
Energy (eV)
PtO2 (Pt4+ ref)
11550 11555 11560 11565 11570 11575-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0Pt powder data
fit components
Inte
nsity
(A.U
.)
Energy (eV)
11550 11555 11560 11565 11570 11575-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0(CH3)2Pt(COD) data
fit components
Inte
nsity
(A.U
.)
Energy (eV)11550 11555 11560 11565 11570 11575
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0Pt(acac)2
data fit components
Inte
nsity
(A.U
.)
Energy (eV)
11550 11555 11560 11565 11570 11575-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0PtO2
data fit components
Inte
nsity
(A.U
.)
Energy (eV)11550 11555 11560 11565 11570 11575
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.00.5% PtGR:TiO2
data fit components
Inte
nsity
(A.U
.)
Energy (eV)
Fig. S5 HERFD-XANES absorption spectra and fits using a pseudo-voigt function for the whiteline and arctangent function for the step. An additional lorentzian peak had to be included in the fitting model of the Pt(acac)2 sample.
Sample: Oxidation number: White line pseudo- R-factor: χ²/ν:
Voigt area (arbitrary units):
Pt powder (ref.) 0 7.1 0.002 0.004(CH3)2Pt(COD) (ref.) +2 11.3 0.002 0.005Pt(acac)2 (ref.) +2 12.2 0.001 0.02PtO2 (ref.) +4 20.9 0.009 0.030.5% PtGR:TiO2 12.5 0.003 0.01
Table S2 fitting results of Pt-L3 edge HERFD–XANES of 0.5% Pt:{001}-anatase, along with four Pt references
0.5% PtGR:TiO2 Pt metallic powder
Pt(COD)(Me)2 PtO2
Fig. S6 Contour plots of the wavelet transform magnitude showing the (k,R) localization of each FT-EXAFS contribution measured at the Pt L3-edge for 0.5%PtGR:TiO2, Pt metallic powder, Pt(COD)(Me)2, and PtO2
4 6 8 10 12-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0 Data fit
k2 (k
) (Å
-2)
Wavenumber (Å-1)0 1 2 3 4 5 6
0
2
4
6
8
10
12
14
16
18
20 data fit
(R
) (Å
-3)
Radial distance (Å)
Scatter Coordination number
S02 R (Å) σ2 (Å2) ΔE0 (eV)
Pt-Pt 12 (defined) 0.77 ±0.04 2.763 ±0.002 0.0042 ±0.0003 7.6 ± 0.4
Fig. S7 Platinum foil EXAFS fitting using only the first Pt-Pt scattering path to determine the amplitude reduction factor (S02). k-
range = 2.8 – 12 ; dk=1 ; R-range = 1.373 – 3.415 ; χ2/ν = 234.12 ; R-factor = 0.42 %
Figure S8 O-Pt-O DFT-optimized structure
Fig. S9 Complete DFT-optimized structures for the Pt reduction by CO reaction with the Ti-O-Pt(COD)-F-Ti structure.
Fig. S10 Proposed mechanism for Pt reduction by CO for the Ti-O-Pt(COD)-O-Ti structure
400 600 800 10000
20
40
60
80P
hoto
n flu
x (µ
Mol
.s-1.m
-2.n
m-1)
Wavelength (nm)
225-387 nm
Xe lamp photon distributionCell area: 38.5 cm2
Figure S11 Xenon lamp photon distribution.
0 10 20 30 400
10
20
30
40
50
60
70
{001}-anatase (support) data fit
Oxygen evolution reaction4-point average
0.5%PtGR:TiO2
data fit
OE
R ra
te (µ
mol
/h)
Time (h)
Fig. S12 OER activity and exponential decay fits of {001}-anatase and 0.5%PtGR:TiO2. First 30 minutes excluded due to gas mixing kinetics in the reactor
Fig. S13 TEM micrographs of 0.5%PtGR:TiO2 after photocatalysis with sacrificial methanol. Only nanoparticles are visible
0 2 4 6 8 100
10
20
30
40
50
0
10
20
Rat
e (µ
mol
/h)
Time (h)
0
5
10
15
20
25
30
35
40
TOF
(h-1)
p(H
2) (m
bar)a)
0 2 4 6 8 10
0
10
20
30
40
50
0
10
20
Rat
e (µ
mol
/h)
Time (h)
b)
p(H
2) (m
bar)
Fig. S14 Backwards reaction rates measured on: a) impregnated 0.5%PtNP:TiO2 and b) support blank ({001}-anatase) showing no noticeable activity.
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