1 Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la

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1 Supporting Information (SI) New Insights Into BiVO 4 Properties as Visible Light Photocatalyst Tamar Saison 1,2, Nicolas Chemin 2, Corinne Chanéac 1, Olivier Durupthy* 1, Laurence Mariey 3, Françoise Maugé 3, Vlasta Brezová 4, Jean-Pierre Jolivet 1 1 Sorbonne Universités, UPMC Univ Paris 06, CNRS, Collège de France, Laboratoire de Chimie de la Matière Condensée de Paris, 11 place Marcelin Berthelot, Paris, France. 2 Service Produits Composites et Revêtement de Surfaces, Saint-Gobain Recherche, 39 quai Lucien Lefranc, BP 135, Aubervilliers, France 3 Laboratoire de Catalyse et Spectrochimie de Caen, ENSICAEN, Université de Caen, CNRS, 6 boulevard Maréchal Juin, Caen, France 4 Institute of Physical Chemistry and Chemical Physics, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, SK Bratislava, Slovakia olivier.durupthy@upmc.fr RECEIVED DATE (to be automatically inserted after your manuscript is accepted if required according to the journal that you are submitting your paper to) Telephone: , Fax: , olivier.durupthy@upmc.fr 1

2 Figure SI-1. a) XPS spectra of BiVO 4 -MS (green) and BiVO 4 -SDS (black) in the S 2s binding energy domain, b) TGA of BiVO 4 -SDS sample with MS detection of H 2 O and SO 2. 2

3 wavenumber (cm -1 ) Figure SI-2. Raman spectra of BiVO 4 -TZ (a), BiVO 4 -TS (b) and BiVO 4 -MS (c) 3

4 Figure SI-3. Experimental diffraction pattern of BiVO 4 -TS (a) and modelled diffractogram without BiO 8 distortion (d Bi-O =4x2.494Å+4x2.450) (b) and with BiO 8 distortion (d Bi- O=3x2.494Å+3x x2.410Å+1x2.390Å) (c) 4

5 SI to 3.4. Determination of generated radicals. The spin trapping agent used, DMPO may form corresponding paramagnetic spin adducts with both photogenerated species, i.e. DMPO-OH and DMPO-O 2. However, alternative non-radical reactions may also produce the detected spin adducts, e.g. formation of DMPO-OH via hydrolysis of DMPO + originating from one-electron oxidation of DMPO. 1 That is why the EPR experiments must be carefully done using blank samples and references to calibrate the concentration results. The formation of DMPO-OH can be directly studied in water and the hydroxyl radical trapped may either come from the interaction between water and photogenerated holes or from the consecutive reactions of superoxide radical anions 2, 3 Upon UV irradiation of the aerated TiO 2 or BiVO 4 suspensions in water in the presence of DMPO, typical four-line EPR spectra were monitored, characterized by spin Hamiltonian parameters a N = mt, a β H = mt; g = attributed to the hydroxyl radical added to DMPO ( DMPO-OH). 3, 4 The second radical DMPO-O - 2 cannot easily be detected in aqueous solvent for main reasons; the stability of superoxide radical anion in water is limited, O 2 is only weakly reactive toward DMPO in aqueous media (the kinetic constant is 8 orders of magnitude lower than that with OH) and the spin adduct is not very stable in water (t 1/2 = 80 s). 5, 6 A good way to avoid such limitation is to replace water by an aprotic solvent such as DMSO. 3, 5, 7 Upon UV irradiation of the aerated TiO 2 or BiVO 4 suspensions in DMSO in the presence of DMPO, twelve-line EPR signal dominated in spectra, characterized by spin Hamiltonian parameters a N = mt, a β H = mt, a γ H = mt; g = attributed to the superoxide radical anion added to DMPO ( DMPO-O 2 ), as is shown in the inset of Figure 9. 3, 6 Another spin adduct was observed in the experimental spectra namely DMPO-OCH 3 produced via photocatalytic reaction pathway involving the DMSO solvent and surface hydroxyl groups/water molecules 4 and the concentrations of the two spin adducts in the different photocatalysts suspensions are determined and reported in the Figure 9. 5

6 30 [ DMPO-adducts] (µmol.l 1 ) all DMPO-adducts DMPO-O 2 DMPO-OCH 3 0 Blank TiO 2 P25 BiVO 4 -MS BiVO 4 -X BiVO 4 -SDS BiVO 4 -ph4 Figure SI-4. Measured DMPO-O 2 - and DMPO-OCH 3 spin adduct concentrations and their sum obtained after UV irradiation (λ max = 365 nm) of aerated DMSO suspensions of different photocatalysts (UV-radiation dose 3 J.cm 2 ). (Photocatalyst concentration 0.25 g.l 1, [DMPO] i = mol.l 1 ). 1. Brezova, V.; Gabcova, S.; Dvoranova, D.; Stasko, A., Reactive Oxygen Species Produced Upon Photoexcitation of Sunscreens Containing Titanium Dioxide (an Epr Study). J. Photochem. Photobiol., B 2005, 79, Hoffmann, M. R.; Martin, S. T.; Choi, W.; Bahnemann, D. W., Environmental Applications of Semiconductor Photocatalysis. Chem. Rev. 1995, 95, Dvoranova, D.; Barbierikova, Z.; Brezova, V., Radical Intermediates in Photoinduced Reactions on Tio2 (an Epr Spin Trapping Study). Molecules 2014, 19, Saison, T.; Gras, P.; Chemin, N.; Chanéac, C.; Durupthy, O.; Brezova, V.; Colbeau-Justin, C.; Jolivet, J.-P., New Insights into Bi2wo6 Properties as a Visible-Light Photocatalyst. J. Phys. Chem. C 2013, 117, Finkelstein, E.; Rosen, G. M.; Rauckman, E. J., Spin Trapping. Kinetics of the Reaction of Superoxide and Hydroxyl Radicals with Nitrones. J. Am. Chem. Soc. 1980, 102, Buettner, G. R.; Oberley, L. W., Considerations in Spintrapping of Superoxide and Hydroxyl Radical in Aqueous Systems Using 5,5-Dimethyl-1-Pyrroline-1-Oxide. Biochem. Biophys. Res. Commun. 1978, 83, Dvoranova, D.; Brezova, V.; Mazur, M.; Malati, M. A., Investigations of Metal-Doped Titanium Dioxide Photocatalysts. Appl. Catal., B 2002, 37,