Photovoltaic effects of nanotubular TiO2/QDS array on direct electron transfer behavior of proteins

• Main Author: Xie, Dan
• Other Authors: Li Changming
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Chemical engineering::Industrial electrochemistry
• Online Access: http://hdl.handle.net/10356/16786
• Institution: Nanyang Technological University

Titanium dioxide (TiO2), a semiconductor metal oxide, has attracted great attentions in recently years due to its unique physical and chemical properties. Under UV light, it can greatly improve the catalytic activity of many proteins. Quantum dots (QDs), known as a group of small band gap semiconductors, have the ability to photosensitize large band gap semiconductors in the visible light. In this project, by using potentiostatic anodization and sequential chemical bath deposition, CdS/TiO2 nanotube arrays were synthesized, which were used as hosting substrate for protein immobilization. The structure of the as-prepared nanostructures was characterized by electron microscopy, energy dispersive X-ray analysis (EDX), X-ray diffraction and FT-IR. The photovoltaic effects of the nanostructure on the direct electrochemistry and catalytic behavior of immobilized proteins were also investigated. Induced by visible light, CdS/TiO2 could greatly enhance the direct electron transfer of proteins. Moreover, it also improved the catalytic activity of the proteins towards hydrogen peroxides. These results indicate that it may be a new way to construct photo-controlled protein biosensor with high sensitivity.