Surface structure of ultrathin copolymer films of ferroelectric vinylidene fluoride (70%) with trifluoroethylene (30%) on graphite

Article

关键词: LANGMUIR-BLODGETT-FILMS;    SCANNING-TUNNELING-MICROSCOPY;    ATOMIC-FORCE MICROSCOPY;    OLIGOMER THIN-FILMS;    STRAIN RELIEF;    2-DIMENSIONAL FERROELECTRICITY;    PHASE-TRANSITION;    POLYMER-FILMS;    SINGLE ATOMS;    MANIPULATION;   

DOI  :  10.1103/PhysRevB.70.155411

来源: SCIE

【 摘 要 】

The structure and local structural distortions, through the polarization manipulation, of crystalline films of ferroelectric vinylidene fluoride (70%) with trifluoroethylene (30%) [P(VDF-TrFE)] copolymer on graphite were studied by scanning tunneling microscopy (STM). A quasispiral twist in C-C bonds with rotations about the polymer chain axis was observed by high-resolution STM, indicating a surface relaxation of the strained copolymer films. Such a relaxation behavior appears to be linked to the observed local dipole rotations accompanied by the reversal of the local polarization with biasing the STM tip. A structure model is proposed based upon the observations.

【 授权许可】

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