Supporting Information for âElectronic Structure of Monoclinic BiVO4â
Supporting Information for “Electronic Structure of Monoclinic BiVO4” Jason K. Cooper,1,2, Sheraz Gul3, Francesca M. Toma1,4, Le Chen1,2, Per-Anders Glans5, Jinghua Guo5, Joel W. Ager,1,2 Junko Yano1,3, Ian D. Sharp1,3* 1
Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
2
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
3
Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
4
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
5
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
* Corresponding author.
Figure S1. XRD of CVD grown BiVO4 (black) thin film grown on FTO coated glass substrate. Also provided are reference peaks of FTO and monoclinic scheelite (ms) BiVO4.
Figure S2. Summary of the structurally optimized unit cell and lattice element positions for ms-BiVO4 used for the DFT calculations in this work.
Figure S3. Oxygen partial charge anisotropy in the ms-BiVO4 lattice of -0.4824 (red) and -0.4847 (blue). Bi: purple, V: green, O(1): red, O(2): blue.
Figure S4. Integrated local density of states of ms-BiVO4, for a) -3.56 to -2.60 eV, b) -1.22 to -0.32 c) 0.32 to 0.00 eV, and d) 2.04 to 2.14 eV. Bi: purple, V: green, O: red.
Figure S5. Cross section of the integrated local density of states for energies between 2.04 and 2.36 eV, corresponding to the conduction band minimum.
Figure S6. O K edge XAS of ms-BiVO4 thin film on FTO (black) and of bare FTO substrate (grey). These measurements confirm that the thickness and conformality of the CVD layer are sufficient to ensure that the substrate signal is fully attenuated and does not interfere with analysis of the BiVO4 thin film.
Figure S7. Integrated local density of states between (a) 6.61 and 7.03 eV, highlighting the Bi 6py orbital oriented along the b lattice vector and (b) 4.96 and 5.50 eV, showing the Bi 6px and 6pz orbitals. Bi: purple, V: green, O: red.
Figure S8. Crystal structure of monoclinic scheelite BiVO4 determined by powder neutron diffraction at 298 K, reported by Sleigh et al. 1.
Figure S9. Schematic energy level diagram of the indirect RIXS mechanism, in which a core electron occupied at V4+ 2p3/2 is excited by photon energy ℎ𝜈 to fill an unoccupied 3d level. A coulomb interaction between the resulting core-hole and the 3d electron results in promotion to higher levels equal to the d-d excitation energy, ℎ𝜈𝑑−𝑑 . Decay of the photoelectron back to fill the core hole results in photon emission of energy ℎ𝜈 − ℎ𝑣𝑑−𝑑 leaving behind an electron above the CB edge. A thorough review of RIXS, including descriptions of indirect and direct RIXS mechanisms, is available in Ref. 2.
Figure S10. X-ray photoelectron spectrum of V 2p3/2 showing both V5+ (green) and V4+ (blue) near the surface of the BiVO4 thin film.
Figure S11. Measurement of the secondary electron cutoff (black) for determination of the ms-BiVO4 work function via extrapolation of a linear fit of the edge to the baseline (gray line).
REFERENCES (1) Sleight, A. W.; Chen, H. Y.; Ferretti, A.; Cox, D. E. Mater. Res. Bull. 1979, 14, 1571. (2) Ament, L. J. P.; van Veenendaal, M.; Devereaux, T. P.; Hill, J. P.; van den Brink, J. Rev. Mod. Phys. 2011, 83, 705.
Joint Center for Artificial Photosynthesis, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
2
Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
3
Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
4
Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
5
Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
* Corresponding author.
Figure S1. XRD of CVD grown BiVO4 (black) thin film grown on FTO coated glass substrate. Also provided are reference peaks of FTO and monoclinic scheelite (ms) BiVO4.
Figure S2. Summary of the structurally optimized unit cell and lattice element positions for ms-BiVO4 used for the DFT calculations in this work.
Figure S3. Oxygen partial charge anisotropy in the ms-BiVO4 lattice of -0.4824 (red) and -0.4847 (blue). Bi: purple, V: green, O(1): red, O(2): blue.
Figure S4. Integrated local density of states of ms-BiVO4, for a) -3.56 to -2.60 eV, b) -1.22 to -0.32 c) 0.32 to 0.00 eV, and d) 2.04 to 2.14 eV. Bi: purple, V: green, O: red.
Figure S5. Cross section of the integrated local density of states for energies between 2.04 and 2.36 eV, corresponding to the conduction band minimum.
Figure S6. O K edge XAS of ms-BiVO4 thin film on FTO (black) and of bare FTO substrate (grey). These measurements confirm that the thickness and conformality of the CVD layer are sufficient to ensure that the substrate signal is fully attenuated and does not interfere with analysis of the BiVO4 thin film.
Figure S7. Integrated local density of states between (a) 6.61 and 7.03 eV, highlighting the Bi 6py orbital oriented along the b lattice vector and (b) 4.96 and 5.50 eV, showing the Bi 6px and 6pz orbitals. Bi: purple, V: green, O: red.
Figure S8. Crystal structure of monoclinic scheelite BiVO4 determined by powder neutron diffraction at 298 K, reported by Sleigh et al. 1.
Figure S9. Schematic energy level diagram of the indirect RIXS mechanism, in which a core electron occupied at V4+ 2p3/2 is excited by photon energy ℎ𝜈 to fill an unoccupied 3d level. A coulomb interaction between the resulting core-hole and the 3d electron results in promotion to higher levels equal to the d-d excitation energy, ℎ𝜈𝑑−𝑑 . Decay of the photoelectron back to fill the core hole results in photon emission of energy ℎ𝜈 − ℎ𝑣𝑑−𝑑 leaving behind an electron above the CB edge. A thorough review of RIXS, including descriptions of indirect and direct RIXS mechanisms, is available in Ref. 2.
Figure S10. X-ray photoelectron spectrum of V 2p3/2 showing both V5+ (green) and V4+ (blue) near the surface of the BiVO4 thin film.
Figure S11. Measurement of the secondary electron cutoff (black) for determination of the ms-BiVO4 work function via extrapolation of a linear fit of the edge to the baseline (gray line).
REFERENCES (1) Sleight, A. W.; Chen, H. Y.; Ferretti, A.; Cox, D. E. Mater. Res. Bull. 1979, 14, 1571. (2) Ament, L. J. P.; van Veenendaal, M.; Devereaux, T. P.; Hill, J. P.; van den Brink, J. Rev. Mod. Phys. 2011, 83, 705.
