高活性氮掺杂介孔二氧化钛的合成及性能研究

doi:10.15541/jim20140125

摘要/Abstract

摘要：

采用水热法, 以聚乙二醇(PEG)为模板, N,N-二甲基甲酰胺为氮源, 制备了氮掺杂的介孔二氧化钛。并用X射线粉末衍射(XRD)、傅立叶红外光谱(FTIR)、BET、透射电子显微镜(TEM)、紫外一可见漫反射谱(DRS)和X射线光电子能谱(XPS)等技术手段对制备样品进行了表征。结果表明: 所合成的样品具有锐钛矿结构,直径约20 nm, 并且具有一定的可见光活性。以甲基橙(MO)为光降解模型, 样品在可见光区表现出了较好的催化活性, 这取决于烷氧基和氮掺杂的协同效应。

关键词: 介孔二氧化钛, 氮掺杂, 光催化

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

王慧蕾, 刘孝恒. 高活性氮掺杂介孔二氧化钛的合成及性能研究[J]. 无机材料学报, 2014, 29(9): 997-1002.

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.

图/表 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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