Bifunction-Integrated Dielectric Nanolayers of Fluoropolymers with Electrowetting Effects

Hao Wu; Hao Li; Ahmad Umar; Yao Wang; Guofu Zhou

doi:10.3390/ma11122474

Bifunction-Integrated Dielectric Nanolayers of Fluoropolymers with Electrowetting Effects

Materials (Basel). 2018 Dec 5;11(12):2474. doi: 10.3390/ma11122474.

Authors

Hao Wu^{1

2}, Hao Li³, Ahmad Umar⁴, Yao Wang⁵, Guofu Zhou^{6

7

8}

Affiliations

¹ Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China. wuhao@scnu.edu.cn.
² Physics of Complex Fluids, Faculty of Science and Technology, MESA+ Institute for Nanotechnology, University of Twente, 7500AE Enschede, The Netherlands. wuhao@scnu.edu.cn.
³ Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China. haoli@scnu.edu.cn.
⁴ Department of Chemistry, Faculty of Science and Arts and Promising Centre for Sensors and Electronic Devices, Najran University, Najran 11001, Kingdom of Saudi Arabia. ahmadumar786@gmail.com.
⁵ Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China. wangyao@m.scnu.edu.cn.
⁶ Guangdong Provincial Key Laboratory of Optical Information Materials and Technology & Institute of Electronic Paper Displays, National Center for International Research on Green Optoelectronics, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China. guofu.zhou@m.scnu.edu.cn.
⁷ Shenzhen Guohua Optoelectronics Tech. Co. Ltd., Shenzhen 518110, China. guofu.zhou@m.scnu.edu.cn.
⁸ Academy of Shenzhen Guohua Optoelectronics, Shenzhen 518110, China. guofu.zhou@m.scnu.edu.cn.

Abstract

Fluoropolymers play an essential role in electrowetting (EW) systems. However, no fluoropolymer possesses the desirable properties of both hydrophobicity and dielectric strength. In this study, for the first time, we report the integration of two representative fluoropolymers-namely, Teflon AF (AF 1600X) and Cytop (Cytop 809A)-into one bifunctionalized dielectric nanolayer. Within this nanolayer, both the superior hydrophobicity of Teflon AF and the excellent dielectric strength of Cytop were able to be retained. Each composed of a 0.5 μm Cytop bottom layer and a 0.06 μm Teflon AF top layer, the fabricated composite nanolayers showed a high withstand voltage of ~70 V (a dielectric strength of 125 V/μm) and a high water contact angle of ~120°. The electrowetting and dielectric properties of various film thicknesses were also systemically investigated. Through detailed study, it was observed that the thicker Teflon AF top layers produced no obvious enhancement of the Cytop/Teflon AF stack.

Keywords: contact angle; dielectric layer; dielectric strength; electrowetting; fluoropolymers.

Abstract

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