Trong bài viết này, vật liệu ống nano TiO2 (TNT) tổ hợp với các tấm nano graphene (Gr) dạng đĩa (nanoplatelete) được chế tạo bằng phương pháp thủy nhiệt trong môi trường kiềm. Hình thái bề mặt và các đặc tính của vật liệu được phân tích bằng hình ảnh hiển vi điện tử truyền qua (TEM), nhiễu xạ tia X (XRD) và phổ dao động Raman. | VNU Journal of Science Natural Sciences and Technology Vol. 36 No. 3 2020 1-9 Original Article Heterostructure of Titanium Dioxide Nanotube Graphene Nanoplatelet with Enhancing Photocatalytic Activity Vo Quang Mai1 Vo Chi Hao1 Nguyen Huu Tho1 Nguyen Xuan Sang2 1 Department of Natural Sciences Education Saigon University 273 An Duong Vuong ward 3 district 5 Ho Chi Minh City Vietnam 2 Department of Electronics and Telecommunication Saigon University 273 An Duong Vuong ward 3 district 5 Ho Chi Minh City Vietnam Received 18 September 2019 Revised 15 April 2020 Accepted 01 August 2020 Abstract In this study the composite of titanium dioxide nanotube TNT and graphene nanoplatelet was hydrothermally synthesized in a sodium hydroxide solution. Morphological and crystalline properties of the synthesized samples were analyzed by transmission electron microscopy TEM X-ray differactometry XRD and Raman spectroscopy. Optical properties were investigated by UV-Vis diffuse reflextance spectra DRS where optical bandgap was determined. Photocatalytic activity of the synthesized samples was evaluated through the degradation of methylene blue in the solution under direct sunlight irradiation. The result showed the enhancement of photocatalytic activity in the composite sample in compare to the bare TNT. After 120 min of irradiation the photocatalytic efficiency of the composite and TNT was 95 and 63 respectively. Mechanism of enhanced activity was supported by DRS measurements in which the composite showed the higher visible light absoption and lower bandgap value. Optical bandgap of the sGr TNT composite was about eV which was notably reduced in compare to that of the bare TNT of eV. Keywords titanium nanotube graphene heterostructure photocatalysis DRS. ____ Corresponding author. Email address sangnguyen@ https 2588-1140 1 2 . Mai et al. VNU Journal of Science Natural Sciences and Technology Vol. 36 No. 3 2020 1-9 Cấu trúc dị
