Supplementary information
Heterolytic splitting of H2 and CH4 on γalumina as a structural probe for defect sites. Jérôme Joubert, Vincent Krakoviack, Françoise Delbecq, Philippe Sautet, Alain Salameh, Christophe Copéret, Jean Marie Basset Laboratoire de Chimie – UMR CNRS 5182 École normale supérieure de Lyon, 46 allée d’Italie, 69364 Lyon Cedex 07, France. Laboratoire de Chimie Organométallique de Surface (UMR 9986 CNRS / ESCPE Lyon) ESCPE Lyon, F-308, 43 Boulevard du 11 Novembre 1918, 69616 Villeurbanne Cedex, France
-1-
a) 1.2
Absorbance
1.0
(1902 &1866) νAl-H 3800-3660 (νOH)
0.8 0.6 v)
0.4
iv) iii)
0.2
ii) i)
0.0
3000
2000
Wave Number b)
1902 cm-1 (νAlH )
(cm-1)
c) 3800-3475 (νOH)
0.2
Absorbance
Absorbance
1866 cm-1 (νAlH)
(v-i) (iv-i) 0.1
(iii-i)
0.04
0.02
0.00
Wave number
(iv-i) (iii-i)
(ii-i) 2000 1900 1800 1700
(v-i)
(ii-i) 3900
3700
3500
Wave number
(cm-1)
3300
(cm-1)
Figure S1. Monitoring the reaction of Al2O3-(500) with H2 at various temperature by IR spectrum spectroscopy: a) IR spectrum of 4000-1700 cm-1 region {(i) Al2O3-(500), (ii) H2 (400 Torr H2) after 1h at 25°C, (iii) after 1h at 100°C, (iv) after 1h at 150°C (v) after treatement under vacuum (10-5 Torr) for 1h at 25°C.} b) Substracted IR spectra (2200-1600 cm-1 region). c) Substracted IR spectra (4100-3200 cm-1 region).
-2-
a)
νOH 3800-3660
0.8
Absorbance
0.6 vii) 0.4
vi) v) iv) iii)
0.2 ii) i)
0.0
3000
2000
Wave number (cm-1) b)
3014 (νCH3-H) 2942 (νCsp3-H) (vii-i)
3800-3475 (νOH)
c)
2900 (νCsp3-H)
0.20
0.14
Absorbance
Absorbance
(vi-i) (v-i)
(iv-i) (iii-i) 0.13 (ii-i)
0.15
0.10 3100
3000
2900
(vii-i) (vi-i) (v-i) (iv-i) (iii-i) (ii-i) 3900
Wave number (cm-1)
3700
3500
3300
Wave number (cm-1)
Figure S2. Monitoring the reaction of Al2O3-(500) with CH4 at various temperature by IR spectrum spectroscopy (The band at 3014 cm-1 correspond to CH4 in the gas phase): a) IR spectrum of 4000-1400 cm-1 region (i) Al2O3-(500) (ii) +400 torr CH4 /1h à 25°C (iii) 1h à 50°C (iv) 1h à 100°C (v) 1h à 150°C (vi) 1h à 10-5 torr / 25°C. b) Substracted IR spectra (32002800 cm-1 region). c) Substracted IR spectra (4000-3200 cm-1 region).
-3-
-22.0 300
260
220
180
140
100
60
20
-20
-60
-100
-140
(ppm)
Figure S3. The 13C CP-MAS solid state NMR spectrum of a γ-alumina treated at 150 °C with 13
C labeled CH4 was recorded under MAS of 10 kHz. The number of scans was 1600, and the
recycle delay was set to 32 s. For the CP step (2 ms), a ramp radio frequency (rf) field centred at 50 kHz was applied on protons, while the carbon rf field was matched to obtain optimal signal. Table S1. 13C chemical shift of small molecules with Al−C bonds. Calculated δ (ppm)
Experimental δ (ppm)
CH3
-8
-8,01
µ-CH3
-12
-5,31
CH2
22
212
molecule [Al(CH3)2(µ-CH3)]2
Al(CH2C6H5)3
(1) Babushkin, D. E. ; Semikolenova, N. V. ; Zakharov, V. A. ; Talsi, E. P. Macromol. Chem. Phys. 201 (2000) 558 ; (2) Zelta, L. ; Gatti, G. Org. Magn. Res. 4 (1972) 585
-4-
