Synthesis of N-doped Mesoporous Titania with High Visible-light Photocatalytic Activity

doi:10.15541/jim20140125

Abstract

Abstract:

N-doped mesoporous titania was synthesized using polyethylene glycol (PEG) as template and Dimethyl Formamide (DMF) as nitrogen source. The physical and photophysical properties of the photocatalyst were characterized by X-ray diffraction (XRD), FTIR, BET, transmission electron microscope (TEM), UV-Vis diffuse re?ectance spectra (DRS), and X-ray photoelectron spectra (XPS). PEG played an important role in the preparation process within mesoporous titania. The N-doped mesoporous titania possessed diameter of ca. 20 nm with anatase crystalline structure, and had absorption in the visible region. N-doped mesoporous titania samples showed excellent photocatalytic activity for methyl orange (MO) degradation under visible light irradiation, which could be attributed to synergistic effect between the retained alkoxyls and the nitrogen doping.

Key words: mesoporous titania, N- doping, photodegraduation

WANG Hui-Lei, LIU Xiao-Heng. Synthesis of N-doped Mesoporous Titania with High Visible-light Photocatalytic Activity[J]. Journal of Inorganic Materials, 2014, 29(9): 997-1002.

Figures/Tables 9

Fig. 1 SAXD patterns of sample a and sample

Fig. 2 XRD patterns of (a) mesoporous tiania and (b-f) N-doped mesoporous tiania with different volume of DMF

Fig. 3 FTIR spectra of (a) mesoporous titania and (b-f) N-doped mesoporous titania with different volume of DMF (DMF Dimethyl Formamide)

Fig. 4 XPS survey spectrum and N1s core level of the sample e

Fig. 5 (A) N2 adsorption-desorption isotherms and pore size distributions (inset) of sample a; (B) N2 adsorption-desorption isotherms and pore size distributions (inset) of sample e

Fig. 6 TEM images of mesoporous titania (sample a) (A, B) and N-doped mesoporous titania (sample e) (C, D, E)

Fig. 7 UV-DRS spectra of mesoporous titania (a) and N-doped mesoporous titania with different volume of DMF and P25 (b-f)

Table 1 Wavelength value obtained from UV-DRS spectra and band gap energy values obtained for the synthesized photocatalysts

Catalyst	λ_g	Band gap energy/eV
P25	387	3.20
a	394	3.14
b	408	3.04
c	410	3.02
d	450	2.76
e	506	2.45
f	475	2.61

Fig. 8 Photocatalytic degradation of MO under visible light irradiation Mesoporous titania (a) and N-doped mesoporous titania with different volume of DMF (b-f)

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