tailieunhanh - Microstructure and optical properties of transition metal (Co, Ni)-DOPED TiO2 nanowires synthesized by solvothermal method

The undoped and transition metal (Co, Ni)-doped TiO2 nanowires were synthesized by simple and low cost solvothermal method and their microstructure and optical properties were investigated based on the fixed doping concentration of 1 at.%. The X-ray diffractometer and highresolution transmission electron microscopy demonstrated that the nanowire had a singlecrystalline rutile structure and grew along the [001] growth direction. | Communications in Physics, Vol. 22, No. 3 (2012), pp. 247-253 MICROSTRUCTURE AND OPTICAL PROPERTIES OF TRANSITION METAL (Co, Ni)-DOPED TiO2 NANOWIRES SYNTHESIZED BY SOLVOTHERMAL METHOD LUU TIEN HUNG, NGUYEN THI MINH, LE THI KIEU NGA, AND NGUYEN THI QUYNH HOA Faculty of Electronics and Telecommunications, Vinh University NGUYEN HONG QUANG Faculty of Physics, Vinh University Abstract. The undoped and transition metal (Co, Ni)-doped TiO2 nanowires were synthesized by simple and low cost solvothermal method and their microstructure and optical properties were investigated based on the fixed doping concentration of 1 at.%. The X-ray diffractometer and highresolution transmission electron microscopy demonstrated that the nanowire had a singlecrystalline rutile structure and grew along the [001] growth direction. The UV-VIS spectroscopy analysis showed that the optical absorption threshold of transition metal doped-TiO2 nanowires was the red-shifted to visible light region compare to the undoped nanowires, indicating promise for visible light photocatalytic and dilute magnetic semiconductor applications. I. INTRODUCTION One-dimensional (1-D) TiO2 nanostructures have been extensively studied for various applications such as photocatalysis, gas sensor and solar cell due to its outstanding photocatalytic properties, non-toxicity, low cost, and chemical stability [1-7]. Recently, several synthesis methods have been developed to grow 1-D TiO2 nanostructures directly on substrate such as vapor-phase deposition [8], template-assisted method [9,10], and electrochemical approaches such as anodization [4-6]. However, most of them require high growth temperature and post-thermal treatment which increases costs significantly. Very recently, well-aligned rutile TiO2 nanowires were synthesized by solvothermal/hydrothermal method at low cost, simple process and large-scale on FTO as well as arbitrary substrates and they show a promising potential application in dye-sensitized solar .