• 文献标题:   Lyotropic Liquid-Crystalline Mesophase of Lithium Triflate-Nonionic Surfactant as Gel Electrolyte for Graphene Optical Modulator
  • 文献类型:   Article
  • 作  者:   BALCI FM, BALCI S, KOCABAS C, DAG O
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF PHYSICAL CHEMISTRY C
  • ISSN:   1932-7447
  • 通讯作者地址:   Bilkent Univ
  • 被引频次:   1
  • DOI:   10.1021/acs.jpcc.7b03622
  • 出版年:   2017

▎ 摘  要

Lithium salt (noncoordinating anions, such as lithium triflate (Ltf)) gel electrolytes may be key for the practical use of electrochemical devices. We introduce a new lyotropic liquid-crystalline (LLC) mesophase using Ltf, a small amount of water (as low as 1.3 water per Ltf), and nonionic surfactant (C18H37(OCH2CH2)(10)OH, C18E10. The LLC phase forms over a broad range of Ltf/C18E10 mole ratios, 2-18. The clear ethanol solution of the ingredients can be either directly spin-coated over a glass substrate to form a gel phase or it can be prepared as a gel by mixing Ltf, water, and C18E10. The mesophase leaches out surfactant molecules at low salt concentrations, but at a salt/surfactant mole ratio of above 8, the phase is homogeneous with a cubic mesostructure, fully transparent in the visible optical region, mechanically flexible, and an effective gel electrolyte. We have observed a large electrostatic doping on graphene with the Fermi energy level of similar to 1.0 eV using Ltf-C18E10 gel electrolytes. The Ltf-based gels demonstrate better properties than commonly used ionic liquid electrolyte in graphene optical modulators. The stability of the new gel electrolytes and their superior performance make them suitable electrolytes for use in graphene-based optical modulators.