School of Chemistry and Environment, Key Lab of Electrochemical Technology on Energy Storage and Power Generation in Guangdong Universities, South China Normal University, Guangzhou 510006, China.
J Hazard Mater. 2010 Apr 15;176(1-3):617-22. doi: 10.1016/j.jhazmat.2009.11.074. Epub 2009 Nov 18.
Tri-phase (anatase, rutile, and brookite), bi-phase (anatase and rutile), and mono-phase (rutile) TiO(2) nanomaterials with different morphologies were successively synthesized using a hydrothermal-hydrolysis method and adjusting the Ti(4+)/Ti(3+) molar ratio in a precursor solution. The properties of the fabricated nanomaterials were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photocatalytic reaction, and other techniques. It has been shown that TiO(2) nanorods can be obtained by increasing the Ti(4+)/Ti(3+) molar ratio in a precursor solution from 1:0 to 0.3:0.7. TiO(2) nanoparticles are formed if the Ti(3+) fraction in the solution is further increased. The selective synthesis of TiO(2) nanomaterials is explained by a decrease in the reaction rate and by changes in acidity with increasing Ti(3+) content. The tri-phase nanorods and bi-phase nanoparticles synthesized with Ti(4+)/Ti(3+) molar ratios from 1:0 to 0.8:0.2 and 0.2:0.8 to 0:1, respectively, have a higher degradation ability with respect to methylene blue aqueous solutions under UV irradiation at ambient temperature compared to purely rutile TiO(2) nanorods synthesized with Ti(4+)/Ti(3+) molar ratios from 0.7:0.3 to 0.3:0.7. The high photocatalytic activity of the multi-phase TiO(2) samples is primarily attributed to their larger band gap and suppressed recombination of photo-generated electron-hole pairs.
采用水热-水解法，通过调节前驱体溶液中 Ti(4+)/Ti(3+)摩尔比，成功合成了具有不同形貌的三相（锐钛矿、金红石和板钛矿）、双相（锐钛矿和金红石）和单相（金红石）TiO(2)纳米材料。采用 X 射线衍射（XRD）、扫描电子显微镜（SEM）、透射电子显微镜（TEM）、光催化反应等技术对所制备纳米材料的性能进行了表征。结果表明，通过增加前驱体溶液中 Ti(4+)/Ti(3+)摩尔比，从 1:0 增加到 0.3:0.7，可以得到 TiO(2)纳米棒。如果进一步增加溶液中的 Ti(3+)分数，则形成 TiO(2)纳米颗粒。随着 Ti(3+)含量的增加，反应速率降低，酸度发生变化，从而解释了 TiO(2)纳米材料的选择性合成。用 Ti(4+)/Ti(3+)摩尔比为 1:0 至 0.8:0.2 和 0.2:0.8 至 0:1 分别合成的三相纳米棒和双相纳米颗粒，在环境温度下用紫外光照射时，对亚甲基蓝水溶液的降解能力高于用 Ti(4+)/Ti(3+)摩尔比为 0.7:0.3 至 0.3:0.7 合成的纯金红石 TiO(2)纳米棒。多相 TiO(2)样品具有较高的光催化活性，主要归因于其较大的带隙和抑制光生电子-空穴对的复合。
