Highly ordered TiO2 nanotube arrays with controllable length for photoelectrocatalytic degradation of phenol
Highly ordered TiO2 nanotube arrays with controllable length for photoelectrocatalytic degradation of phenol
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DOI：
10.1021/jp0772732
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发表时间：
2008-01-10
影响因子：
3.7
通讯作者：
Fujishima, Akira
中科院分区：
文献类型：
--
作者：
Liu, Zhaoyue;Zhang, Xintong;Fujishima, Akira
通过恒电位阳极氧化制备的高度有序的TiO2纳米管阵列显示出相当大的改善TiO2薄膜中光生电子输运的潜力，因为有序的结构可以提供单向的电通道并减小晶界。本文报道了不同长度的高度有序TiO2纳米管阵列在苯酚光电催化降解中的应用。纳米管阵列的长度可以由电解质介质、阳极氧化时间或两者共同控制。光电催化活性与纳米管阵列的长度有关。在3.1 mW/cm(2)的紫外光照射下，短纳米管阵列表现出比长纳米管阵列更好的光电催化活性，这可以解释为重组效应的减弱。与具有相同厚度和几何面积的P25 TiO2颗粒膜相比，纳米管阵列由于改善了电子传递和减少了电荷重组，对母体钛衬底的附着力更强，对苯酚的降解具有更好的光电催化活性。这种优越的电子传递进一步得到了苯酚降解过程中显著增强的阳极光电流响应的支持。
Highly ordered TiO2 nanotube array prepared by a potentiostatic anodization shows a considerable potential for improving the transport of the photogenerated electrons in the TiO2 film, since the ordered architecture can provide a unidirectional electric channel and reduce the grain boundaries. Here, we report on the application of highly ordered TiO2 nanotube arrays with different lengths for the photoelectrocatalytic degradation of phenol. The lengths of the nanotube arrays can be controlled by the electrolyte media, anodization time, or both. The photoelectrocatalytic activity shows a dependence on the length of the nanotube arrays. Under 3.1 mW/cm(2) irradiance of ultraviolet light, a short nanotube array shows better photoelectrocatalytic activity than a long nanotube array, which can be explained by the reduced recombination effects. When compared with a P25 TiO2 particulate film with similar thickness and geometric area, the nanotube array shows a stronger attachment to the parent titanium substrate and a better photoelectrocatalytic activity for phenol degradation owing to the improved electron transport and reduced charge recombination. This superior electron transport is further supported by the remarkably enhanced anodic photocurrent response in the degradation of phenol.