Thermal stability of titania nanotube arrays

• Main Author: Wang, Zhenxian
• Other Authors: Sam Zhang Shanyong
• Format: Final Year Project
• Language: English
• Published: 2010
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/39394
• Institution: Nanyang Technological University

Anodic titania nanotube arrays have been extensively employed in dye-sensitized solar cells, as a result of fast electron transport and suppressed electron recombination. Since the anatase structure of titania is preferred in this application, the as-grown amorphous nanotubes are normally undertaken annealing at high temperature. In view of this, the thermal stability of titania nanotube arrays is essential in determining the performance of solar cells. In this final year project, titania nanotube arrays were annealed at different temperatures (i.e., 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, and 800 °C) for 3 h to study the thermal stability. The results indicate the nanotube arrays on the substrate were stable up to 600 °C, whereas the standalone membranes were still stable over 600 °C, and even up to 800 °C. This can be attributed to the titanium substrate which facilitates the formation of rutile structure during annealing. Therefore, in view of application in dye-sensitized solar cells, the nanotube arrays on the substrate have to be annealed below 600 °C, whereas the standalone membranes can be annealed over 600 °C while below 800 °C for higher crystallinity.