Maximizing the Photocatalytic Activity of Metal-Organic Frameworks with Aminated-Functionalized Linkers: Substoichiometric

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1 Electronic Supporting Information Maximizing the Photocatalytic Activity of Metal-Organic Frameworks with Aminated-Functionalized Linkers: Substoichiometric effects in MIL-125-NH 2 Matthew Chambers,,# Xia Wang,,# Laura Ellezam,, Ovidiu Ersen, ǁ Marc Fontecave,,# Clément Sanchez,,# Laurence Rozes *, and Caroline Mellot-Draznieks *,# Laboratoire de Chimie des Processus Biologiques, UMR 8229 CNRS, UPMC Univ Paris 06, Collège de France, 11 Marcelin Berthelot, Paris Cedex 05, France Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris, 4 Place Jussieu, Cedex 05, France ǁ Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), UMR 7504 CNRS- Université de Strasbourg (UdS), 23 rue du Loess, Strasbourg Cedex 08, France # Institut de Chimie du Collège de France, Collège de France, 11 Marcelin Berthelot, Paris Cedex 05, France Corresponding authors: laurence.rozes@upmc.fr, caroline.mellot-draznieks@college-defrance.fr C quantitative solid state NMR analysis 2. X-Ray Diffraction, SEM and BET of the MIL-125-NH 2 -% solids 3. UV/Vis Spectroscopy 4. Photocatalytic assays and 1 H NMR detection of benzalcohol 5. Electron Spin Resonance S1

2 1. 13 C quantitative solid state NMR analysis Figure S1. 13 C quantitative solid-state NMR spectrum of the MIL-125-NH 2-70% sample. Symbols: : spinning side band; : assignments to the 13 C of bdc linkers; : assignments to the 13 C of bdc-nh 2 linkers. Framed figure: spectrum area used for the quantification of the bdc-nh 2 and bdc linkers, in MIL-125-NH 2-20% (experimental result bdc:bdc-nh 2 : 80:20 ±5%), MIL-125-NH 2-46% (experimental result bdc:bdc-nh 2 : 54:46 ±5%) and MIL-125- NH 2-70% (experimental result bdc:bdc-nh 2 : 30:70 ±5%). S2

3 2. X-Ray Diffraction, SEM and BET of the MIL-125-NH 2 -% solids S3

4 Figure S2. Scanning electron microscopy (SEM) images and X-Ray powder diffraction (PXRD) patterns show that all MIL-125-NH 2 -% samples all have a very good crystallinity and are isostructural to the parent non-aminated MIL-125 material (See: Dan Hardi, M.;Serre, C.; Frot, T.; Rozes, L.; Maurin, G.; Sanchez, C.; Férey, G. J. Am. Chem. Soc. 2009, 131, ). From the SEM images one can see that the crystal shape is well defined and preserved throughout the whole range of aminated linkers content, with similar crystal sizes from one sample to another. S4

5 3. UV/Vis Spectroscopy Figure S3. a) Tauc plots for the mixed-linker MIL-125-NH 2 -% solids used in order to calculate the optical band gaps. They are calculated under the hypothesis that absorption follows (Ahv) 2 = α(hν-e g ) where A is the absorbance and E g, the band gap. b) Optical band gaps measured for the series of mixed-linker MIL-125-NH 2 -% samples as a function of the bdc-nh 2 content. The aminated linkers afford an increase in the energy level of the valence band localized on the organic units, whilst the energy of the conduction band localized on the Ti-based nodes remains unchanged. This change does not depend on the amount of bdc-nh 2 vs bdc since sub-stoichiometric amounts of bdc-nh 2 afforded the same band gap decrease in the resulting materials.(see: C.H. Hendon et al., C. J. Am. Chem. Soc. 2013, 135, ). S5

6 4. Photocatalytic assays and 1 H NMR detection of benzaldehyde Error in Photocatalysis Measurements: To evaluate the error and reproducibility of our photocatalytic measurements, we assessed three different conditions in triplicate. Based on the above analysis, a percent standard deviation of < 10% can be assigned. Rate of Photocatalytic Benzaldehyde Production by MIL-125-NH 2-100% (nmols hr 1 mg 1 ): Wavelength λ > 325 nm λ > 415 nm λ > 450 nm Run Run Run Std Dev %Std Dev 6.0% 1.8% 2.0% Figure S4. Benzaldehyde production from benzylalcohol under photocatalytic conditions (λ > 415nm) with MIL-125-NH 2 -% (blue rhombs: 0% NH 2 ; green squares: 20% bdc-nh 2 ; yellow triangles: 46% bdc-nh 2 ; orange circles: 70% bdc-nh 2 ; red rhombs: 100% bdc-nh 2 ). Benzyl alcohol diffusion into the material was ruled out as the y-intercept of the kinetic traces of benzaldehyde evolution are close to the value of trace benzaldehyde initially present in the benzyl alcohol solvent. Limitations in benzyl alcohol diffusion would result in an initial burst of catalysis faster than the steady state rate, resulting in a more positive value for the y- intercept. S6

7 Figure S5. 1 H NMR spectrum of benzaldehyde production reaction under photolytic conditions (λ >415 nm, 8 hours irradiation duration) with the MIL-125-NH 2-100% material, using CD 3 CN as NMR solvent and toluene as internal standard. 5. Electron Spin Resonance (ESR) Figure S6: Typical ESR spectra recorded at 77K and 298 K of UV irradiated MIL-125-NH 2 100% impregnated with benzyl alcohol. S7