Effect of surface treated MWCNTs and BaTiO3 nanoparticles on the dielectric properties of a P(VDF-TrFE) matrix

Abstract

High dielectric constant and low loss flexible piezoelectric thin films were successfully synthesized using surface treated multi-walled carbon nanotubes (SMWCNTs) and BaTiO3 nanoparticles (SBTO NPs) as fillers and poly (vinylidenefluoride-trifluoroethylene) (P(VDF-TrFE)) as a matrix. The discrete and insulated SMWCNTs and SBTO NPs were achieved through a chemical reaction with the α-terpineol solution. The surface treatment played a vital role in reducing the dielectric loss by insulating the material surface with OH functional groups. The as-prepared P(VDF-TrFE)-SBTO-SMWCNTs thin films were characterized in terms of surface morphology, crystalline structure, and electrical properties. The PBM3 [(P(VDF-TrFE)-SBTO-SMWCNTs (0.01 wt%)] samples revealed a maximum dielectric constant of 71 and a relatively low loss of 0.045 at a frequency of 1 kHz. Moreover, the film exhibited a very low conductivity of 19.45 μS/m at 105 Hz and a low leakage current density of 3.91 × 10−9 at an applied voltage of 100 V. These results suggest the high breakdown strength for the as-prepared thin films. The enhanced dielectric properties can be attributed to superior interfacial polarization and surface treatment of the materials.