Theoretical Kinetic Analysis of Heterogeneous Photocatalysis by TiO2 Nanotube Arrays: the Effects of Nanotube Geometry on Photocatalytic Activity

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• 作者：Baoshun Liu ; Kazuya Nakata ; Shanhu Liu ; Munetoshi Sakai ; Tsuyoshi Ochiai ; Taketoshi Murakami ; Katsuhiko Takagi ; Akira Fujishima
• 刊名：The Journal of Physical Chemistry C
• 出版年：2012
• 出版时间：April 5, 2012
• 年：2012
• 卷：116
• 期：13
• 页码：7471-7479
• 全文大小：479K
• 年卷期：v.116,no.13(April 5, 2012)
• ISSN：1932-7455

文摘

TiO₂ nanotube arrays are important functional materials in photocatalysis. Compared with other TiO₂ materials, the geometrical parameters of the nanotubes in an array significantly affect photocatalytic activity, but how they do this remains unclear. In the present work, a simple theoretical kinetic model to study the effects of nanotube diameter, wall thickness, and length on the photocatalytic activity of TiO₂ nanotube arrays is developed, in which reactant (O₂) transport is considered. The photocatalytic activity first increases and then decreases as the diameter and wall thickness of the nanotubes increase because of changes in light absorption, surface area, and reactant transport. The photocatalytic activity increases, and then reaches saturation as the nanotube length increases, which is mainly influenced by the change of light absorption along the nanotube. The present kinetic model agrees well with experimental results and clearly explains the photocatalytic activity of TiO₂ nanotubes, helping us to understand nanotube photocatalysis.