Supporting Information

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1 Supporting Information Wiley-VCH Weinheim, Germany

2 Supporting Information Synergistic Effects of B, N Co-doping on the Visible Light Photocatalytic Activity of Mesoporous TiO 2 Gang Liu a,b, Yanning Zhao a, Chenghua Sun a, Feng Li a, Gao Qing Lu b * and Hui-Ming Cheng a * a Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang , China b ARC Centre of Excellence for Functional Nanomaterials, School of Engineering and Australian Institute of Bioengineering and Nanotechnology, The University of Queensland, Qld. 4072, Australia Corresponding authors: maxlu@uq.edu.au (G. Q. Lu); Tel: ; Fax: cheng@imr.ac.cn (H-M Cheng);

3 Table The physicochemical properties of the undoped titania (MT), nitrogen doped titania (N-MT), 10 atom% boron doped titania (BH-MT) and nitrogen codoped titania with 10 atom% boron (N-BH-MT). a calculated by Sherrer equation with anatase (101): D=0.89 λ / β cosθ. λ =1.5405nm, β=full width at half maximum value, θ = diffraction angle. b A, anatase; B, brookite, the phase content calculated from the equation: W A = K A A A /(K A A A +K B A B ), W B = 1-W A, A A, A B are the integral intensity of anatase (101) and brookite (121), K A = 0.886, K B = Figure-S1.XRD patterns of the photocatalysts obtained: 10 atom% boron doped titania (a), nitrogen codoped titania with 10 atom% boron (b), undoped titania (c) and nitrogen doped titania (d).

4 Figure-S2.N 2 adsorption isotherms and pore size distributions of the undoped titania (MT), nitrogen doped titania (N-MT), 10 atom% boron doped titania (BH-MT) and nitrogen codoped titania with 10 atom% boron (N-BH-MT).

5 (A) (B) 10 nm (C) 10 nm (D) 10 nm 10 nm Figure-S3.TEM images of 10 atom% boron doped titania (A and B) and nitrogen codoped titania with 10 atom% boron (C and D).

6 Figure-S4.Raman spectra of samples: (a) nitrogen doped titania, (b) nitrogen codoped titania with 2 atom% boron, (c) nitrogen codoped titania with 6 atom% boron, (d) nitrogen codoped titania with 10 atom% boron. Figure-S5.XRD spectra of samples: (a) nitrogen doped titania, (b) nitrogen codoped titania with 2 atom% boron, (c) nitrogen codoped titania with 6 atom% boron, (d) nitrogen codoped titania with 10 atom% boron.

7 Computational details: In each case, slab models (3 3, as shown in Figure 4 1) with 7 atomic layers are employed for clean (001) surface. All the thicknesses of the vacuum used in these models are more than 20 Å. Two possible adsorption sites of B are considered, the bridging site between two Ti atoms and the central site of four Ti atoms, as shown in Figure 4 1) (B) and (E). Two dopant concentrations are considered, with the coverage of 1/6 for the bridging site and 1/4 for the central site. Based on our tests (1 1 slab and 3 3 slab), the concentration plays an important role on the numbers of electrons per ev, while its effect on the position of states is pretty slight. Full optimizations are carried out using density functional theory (DFT) within the generalized-gradient approximation (GGA) [1], with the exchange-correlation functional of Perdew-Burke-Ernzerhof (PBE) [2, 3], with the numerical double-numerical polarization (DNP) basis set embedded in the Dmol3 code [4, 5]. Estimated errors from the PBE functional with the efficient DNP basis set was supposed to be lower than that with hybrid B3LYP/6-31G** functional according to Delley s test [5]. To test the above model, we have carefully calculated the DOS of bulk anatase TiO 2 and we found that there are three regions in the range of to 4.78 ev, with lower valence band (VB) located about ev to ev, upper VB around ev to 0.00 ev, and conduction band (CB) around 2.00 ev to 4.78 ev. The band width of upper VB is 4.82 ev, which is highly consistent with early XPS result (4.75 ev) [6], and comparable to Asahi s result (5.05 ev from FPLAPW [7]), suggesting that our calculations are good enough for the qualitative analysis presented in this paper. References: [1] W. Kohn and L. J. Sham, Phys. Rev. B, 1965, 140, A1133. [2] J. P. Perdew, K. Burke, and M. Eernzerhof, Phys. Rev. Lett., 1996, 77, 3865.

8 [3] G. Kresse, and J. Joubert, Phys. Rev. B, 1999, 59, [4] B.J. Delley, J. Chem. Phys. 1990, 92, 508. [5] B.J. Delley, J. Chem. Phys. 2000, 114, [6] R. Sanjinés, H. Tang, H. Berger, F. Gozzo, G. Margaritondo, F. Lévy, J. Appl. Phys. 1994, 75, [7] R. Asahi, Y. Taga, W. Mannstadt, A.J. Freeman, Phys. Rev. B 2000, 47, The fitting routing and parameters for XPS spectra of B 1s, Ti 2p 3/2, N 1s We conducted the fitting by employing special fitting software XPSPEAK41 for XPS peak fitting, where parameters such as background type (Linear, Shirley, Tougaard) peak type (s, p, d, f), FWHM, peak shape (Lorentzian-Gaussian) are considered. The background type used in our fitting routing is Linear. All fitted peaks are kept in shape of 30% Lorentzian-Gaussian. The FWHMs of fitted peaks for all N 1s and Ti 2p are 1.3 ev. The FWHMs of B 1s fitted peaks in Figure 3 are 1.5 ev (a), 1.3 ev (b) and 1.5 ev (c), respectively.