title: High quantum yield ZnO quantum dots synthesizing via an ultrasonication microreactor method.
abstract: Green emission ZnO quantum dots were synthesized by an ultrasonic microreactor. Ultrasonic radiation brought bubbles through ultrasonic cavitation. These bubbles built microreactor inside the microreactor. The photoluminescence properties of ZnO quantum dots synthesized with different flow rate, ultrasonic power and temperature were discussed. Flow rate, ultrasonic power and temperature would influence the type and quantity of defects in ZnO quantum dots. The sizes of ZnO quantum dots would be controlled by those conditions as well. Flow rate affected the reaction time. With the increasing of flow rate, the sizes of ZnO quantum dots decreased and the quantum yields first increased then decreased. Ultrasonic power changed the ultrasonic cavitation intensity, which affected the reaction energy and the separation of the solution. With the increasing of ultrasonic power, sizes of ZnO quantum dots first decreased then increased, while the quantum yields kept increasing. The effect of ultrasonic temperature on the photoluminescence properties of ZnO quantum dots was influenced by the flow rate. Different flow rate related to opposite changing trend. Moreover, the quantum yields of ZnO QDs synthesized by ultrasonic microreactor could reach 64.7%, which is higher than those synthesized only under ultrasonic radiation or only by microreactor.
authors.affiliation: College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China; Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, China. Electronic address: ywm13@163.com.
authors.forename: Weimin
authors.initials: W
authors.lastname: Yang
authors.affiliation: College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China; Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, China.
authors.forename: Huafang
authors.initials: H
authors.lastname: Yang
authors.affiliation: College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China; Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, China; Institute 53 of China's Ordnance Industry, Jinan 250031, China.
authors.forename: Wenhao
authors.initials: W
authors.lastname: Ding
authors.affiliation: College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China; Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Jiangsu Key Laboratory of Advanced Laser Materials and Devices, School of Physics and Electronic Engineering, Jiangsu Normal University, Xuzhou 221116, China.
authors.forename: Le
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China; Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, China.
authors.forename: Lixi
authors.initials: L
authors.lastname: Wang
authors.affiliation: Institute 53 of China's Ordnance Industry, Jinan 250031, China.
authors.forename: Mingxun
authors.initials: M
authors.lastname: Yu
authors.affiliation: College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009, China; Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites, Nanjing Tech University, Nanjing 210009, China. Electronic address: ngdzqt@163.com.
authors.forename: Qitu
authors.initials: Q
authors.lastname: Zhang
keywords: Colloidal quantum dots; Microreactor; Ultrasonic; Zinc oxide