tailieunhanh - Effect of annealing temperature on photoluminescence emission and photocatalytic activity of hydrothermal ZnO nanorods

This work reports photoluminescence evolution of hydrothermally homogeneous ZnO nanorods under thermal annealing at various temperatures. The crystalline structure and morphology of synthesized samples were characterized by X-ray diffractometry and Scanning Electron Microscopy. | VNU Journal of Science: Mathematics – Physics, Vol. 35, No. 1 (2019) 13-20 Original article Effect of Annealing Temperature on Photoluminescence Emission and Photocatalytic Activity of Hydrothermal ZnO Nanorods Nguyen Xuan Sang* Department of Electronics and Telecommunication, Saigon University, 273 An Duong Vuong, Ward 3, District 5, Ho Chi Minh city, Vietnam Received 18 November 2018 Revised 08 January 2019; Accepted 20 January 2019 Abstract: This work reports photoluminescence evolution of hydrothermally homogeneous ZnO nanorods under thermal annealing at various temperatures. The crystalline structure and morphology of synthesized samples were characterized by X-ray diffractometry and Scanning Electron Microscopy. The optical properties induced by defect state transitions were investigated by photoluminescence emission. Besides defect states induced emissions in the visible range, the photocatalytic activity of annealed samples was evaluated which indicated that the higher visible photoluminescence intensity gives the better catalytic activity. Keyword: ZnO nanorod, thermal treatment, photoluminescence, photocatalyst. 1. Introduction With a wide bandgap ( eV) and large exciton binding energy (60 meV) at room temperature, ZnO is one of the most interesting oxide semiconductors which has received huge attention from scientists worldwide in many application aspects such as ultraviolet (UV) laser, white light emitting diode (LED), photocatalyst, and sensor [1-3]. Depending on fabrication technique, many types of nano-size ZnO morphology could be obtained such as nanoparticle, nanowire, micro/nanorod, mirodisk. In semiconductor technology and application, one-dimensional ZnO nanostructure such as nanowire, nanorod is technically important due to the unipolar characteristics which could play a crucially role as interconnects in nanoscale electronic devices. __ Corresponding author. E-mail address: sangnguyen@ https// .