Preparation of ZnO Janus particles by Pickering emulsion

• Main Authors: Ming-han Zhong, 鍾明翰
• Other Authors: 陳志恆
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/8s98q7

碩士 === 國立臺北科技大學 === 資源工程研究所 === 101 === The aim of this study is the preparation of Janus particles by Pickering emulsion. The Janus particle contains silicon dioxide as a core layer and the zinc oxide as a shell layer. Comparing with traditional “Microfluidic methods” , Janus particles with uniform size can be prepared with this method. Since the silicon dioxide is hydrophilic, it is difficult to control the area of each sides of the Janus particles. By Pickering emulsion , it is possible to control the structure of Janus particle. In this study, we used cationic surfactant DDAB to modify the silica surface. By this surface modification, one can control the contact angle between particles and wax phase. Then, we synthesize a ZnO shell structure on SiO2 core by liquid-phase precipitation method. After removing wax by THF, Janus particle with silicon dioxide as a core layer and the zinc oxide as a shell layer can be prepared.The Janus particles were characterized by SEM, EDS and XRD. Experiment results show that, increasing the amount of the absorbed , the particle became more hydrophobic. The W/O ratio has significant effect on the stability of emulsion suspension. Increasing the amount of the oil phase will destabilize emulsion suspension. The SEM imagine showed that the Janus particles consist of one side covered with ZnO nanoparticles while the other side of particle was silica. The XRD and EDS imagine also show that the ZnO is of crystalline structure. Comparing with traditional method, this study demonstrated that Janus particles with controllable morphology can be prepared.