Импедансная спектроскопия электропроводящих композиционных материалов на основе микроволокон сополимера поливинилиденфторида с трифторэтиленом, модифицированных полипирролом

The impedance spectra of composite nonwoven materials based on nano- and microfibers of polyvinylidene fluoride-trifluoroethylene copolymer modified by polypyrrole with different doping degree were studied in the frequency range 1000 Hz-5 MHz. It was found that an increase in the doping degree of polypyrrole coating of nanofibers leads to a decrease in the imaginary and real components of the electrical impedance. Regardless of their magnitude, the shape of the hodographs is close to circular arc resting on the ReZ axis, which allows us to consider the studied material as a nanocomposite polymer electrolyte whose dielectric characteristics can be reversibly changed.

The development of poly(ethylene oxide) reinforced with a nanocellulose-based nanocomposite polymer electrolyte in dye-sensitized solar cells

Here, we describe a nanocomposite polymer electrolyte prepared using a solution casting technique.

Preparation of Nanocomposite Polymer Electrolyte via In Situ Synthesis of SiO2 Nanoparticles in PEO

Composite polymer electrolytes provide an emerging solution for new battery development by replacing liquid electrolytes, which are commonly complexes of polyethylene oxide (PEO) with ceramic fillers. However, the agglomeration of fillers and weak interaction restrict their conductivities. By contrast with the prevailing methods of blending preformed ceramic fillers within the polymer matrix, here we proposed an in situ synthesis method of SiO2 nanoparticles in the PEO matrix. In this case, robust chemical interactions between SiO2 nanoparticles, lithium salt and PEO chains were induced by the in situ non-hydrolytic sol gel process. The in situ synthesized nanocomposite polymer electrolyte delivered an impressive ionic conductivity of ~1.1 × 10−4 S cm−1 at 30 °C, which is two orders of magnitude higher than that of the preformed synthesized composite polymer electrolyte. In addition, an extended electrochemical window of up to 5 V vs. Li/Li+ was achieved. The Li/nanocomposite polymer electrolyte/Li symmetric cell demonstrated a stable long-term cycling performance of over 700 h at 0.01–0.1 mA cm−2 without short circuiting. The all-solid-state battery consisting of the nanocomposite polymer electrolyte, Li metal and LiFePO4 provides a discharge capacity of 123.5 mAh g−1, a Coulombic efficiency above 99% and a good capacity retention of 70% after 100 cycles.