Visible light-active boron doped TiO2 nanotube arrays (B/TNTs) were synthesized by adding NaBF4 in anodic oxidation electrolyte.The photocatalytic properties to methylene blue(MB) solution were investigated under visible light irradiation.FE-SEM analysis showed that the morphology of B/TNTs was obviously different.EDS,XPS and FTIR analysis indicated that boron was incorporated into the TNTs lattice to form B-O-Ti bond.B doping could effectively promote the formation of active group Ti-OH on the surface of TiO2,decrease the band gap energy and make the absorption edges of the samples red-shifting.Such effect became stronger with the increase of the B doping concentration.XRD analysis indicated that B doping promoted the growth of anatase grains.The doped TiO2 nanotubes can form anatase phase as pure one when calcined at 550 ℃.The B/TNTs with an optimal photocatalytic activity were fabricated with the NaBF4 concentration of 0.6％(w/w).The photocatalytic degradation rate of MB in 4 h increased from 39.90％ for TNTs without NaBF4 addition to 69％ for B/TNTs,and their photocatalytic degradation ability is basically unchanged after using 10 times.The total organic carbon(TOC) removal rates indicated that the MB can be efficiently mineralized under visible light illumination.%在阳极氧化电解液中添加NaBF4制得了具可见光活性的B掺杂TiO2纳米管阵列(B/TNTs).采用扫描电镜(FE-SEM)、能谱仪(EDS)、X射线衍射(XRD)、傅立叶红外光谱(FTIR)、紫外-可见漫反射光谱(UV-Vis DRS)以及X射线光电子能谱(XPS)对样品进行表征,以亚甲基蓝(MB)的光催化降解为目标反应评价其光催化活性.结果表明:添加NaBF4后,TiO2纳米管表面形貌变化较大;B掺入到TiO2品格中形成B-O-Ti键;B掺杂使得TiO2纳米管表面羟基量增加、光学带隙能减小、光吸收阀值红移,且B掺杂量越多,其相应值的变化量越大;B掺杂能促进TiO2锐钛矿相的发育,纳米管经550℃煅烧后仍保持未掺杂样品的锐钛矿相结构;NaBF4的最佳添加量为0.6％(w/w)时,所得样品光催化活性最佳,可见光下光催化降解MB的4h降解率由未添加的39.90％提高至75.15％,且反复使用10次后其光催化性能基本保持不变;总有机碳(TOG)分析结果表明,MB在可见光下能被B/TiO2有效矿化.
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