Noeiaghaei T, Yun J-H, Nam S W, Zoh K D, Gomes V G, Kim J O, Chae S R
School of Chemical and Biomolecular Engineering, The University of Sydney, NSW 2006, Australia.
Nanomaterials Centre, School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland 4072, Australia.
Water Sci Technol. 2015;71(9):1301-9. doi: 10.2166/wst.2015.078.
The effects of geometrical characteristics such as surface area (SA) and porosity of TiO2 nanotube arrays (TNAs) on its photocatalytic activity were investigated by applying variable voltages and reaction times for the anodization of Ti substrates. While larger SA of nanotubes was observed under higher applied potential, the porosity of TNAs decreased by increasing anodizing voltage. Under applied potential of 80 V, the SA of TNAs increased from 0.164 to 0.471 m2/g as anodization time increased from 1 to 5 hours, respectively. However, no significant effect on the porosity of TNAs was observed. On the other hand, both SA and porosity of TNAs, synthesized at 60 V, increased by augmenting the anodization time from 1 to 3 hours. But further increasing of anodization time to 5 hours resulted in a decreased SA of TNAs with no effect on their porosity. Accordingly, the TNAs with SA of 0.368 m2/g and porosity of 47% showed the highest photocatalytic activity for degradation of 4-chlorobenzoic acid (4CBA). Finally, the degradation of refractory model compounds such as carbamazepine and bisphenol-A was tested and more than 50% of both compounds could be degraded under UV-A irradiation (λmax=365 nm).
通过对钛基底进行阳极氧化时施加可变电压和反应时间，研究了二氧化钛纳米管阵列（TNA）的表面积（SA）和孔隙率等几何特征对其光催化活性的影响。虽然在较高的施加电位下观察到纳米管的表面积更大，但TNA的孔隙率随着阳极氧化电压的增加而降低。在80V的施加电位下，随着阳极氧化时间分别从1小时增加到5小时，TNA的表面积从0.164增加到0.471m²/g。然而，未观察到对TNA孔隙率有显著影响。另一方面，在60V下合成的TNA的表面积和孔隙率，随着阳极氧化时间从1小时增加到3小时而增加。但将阳极氧化时间进一步增加到5小时导致TNA的表面积减小，而对其孔隙率没有影响。因此，表面积为0.368m²/g且孔隙率为47%的TNA对4-氯苯甲酸（4CBA）的降解表现出最高的光催化活性。最后，测试了卡马西平和双酚A等难降解模型化合物的降解情况，在UV-A辐射（λmax=365nm）下，两种化合物均可降解超过50%。
