Tunable Thermal Conductivity of Ferroelectric P(VDF-TrFE)Nanofibers via Molecular Bond Modulation

摘要

Dipoles in ferroelectric copolymer P(VDF-Tr FE)can be driven by electric field,introducing phonon transport modulations via polarizing molecular chains.The thermal conductivity in single 75/25 P(VDF-Tr FE)nanofibers is found to increase with electric field related phonon renormalization,resulted from change in vibrational assignment excited by polarization process.This is evidenced by a direct change of bond energy and bond length in 75/25P(VDF-Tr FE)nanofibers from Raman characterization under polarization electric field.The experimental results provide further intuitive evidences that the size of ferroelectric polymers could directly affect the ferroelectricity from the size-dependent thermal transport measurement.