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论文类型：期刊论文

发表时间：2008-09-22

发表刊物：SEPARATION AND PURIFICATION TECHNOLOGY

收录刊物：SCIE、EI、Scopus

卷号：62

期号：3

页面范围：668-673

ISSN号：1383-5866

关键字：boron doping; TiO2 nanotube arrays; potentiostatic anodization; visible photoelectrochemical activity

摘要：The boron-doped TiO2 nanotube arrays were fabricated by potentiostatic anodization of titanium in an aqueous electrolyte containing fluoride ion and sodium fluoroborate (NaBF4). The highly ordered nanotube arrays with an inner pore diameter of approximately 80 nm and a length of 1.4 mu m are obtained. X-ray photoelectron spectroscopy (XPS) data indicate that the boron atoms are successfully incorporated into the TiO2 matrix, forming Ti-B-O bond in the sample with small amount of boron (1.5 at.%), and the chemical environment surrounding boron is more similar to that in B2O3 in the samples with larger amounts of boron (3.1 and 3.8 at.%). The B-doped TiO2 nanotube arrays with a mixture of anatase phase and very little rutile phase upon thermal annealing at 500 degrees C for 2 h were identified by X-ray diffraction (XRD). Red shifts and enhanced absorption intensities in both UV and visible light regions are observed in the spectra of UV-vis absorption of B-doped samples. The B-doped nanotube arrays show improved photochemical capability under both simulated sunlight and UV irradiation. By comparison, the sample with 3.1 at.% of boron exhibits the best photoelectrochemical properties, and its photocurrent densities under simulated sunlight and UV irradiation are approximately 1.17 and 1.27 times of those of TiO2 nanotube arrays, respectively. The visible photoelectrocatalytic (PEC) activities of the prepared electrodes were evaluated using atrazine as a test substance under simulated sunlight irradiation. The kinetic constant of PEC degradation of atrazine using B-doped electrode with 3.1 at.% of boron is 53% higher than that using non-doped one. A synergetic effect of the photocatalytic (PC) and electrochemical (EC) processes is observed. (C) 2008 Elsevier B.V. All rights reserved.