Synthesis of Polymer-based ZnO/TiO2 NCs Flexible Sheets as High Dielectric Materials

Abstract

Polymer-based ZnO/TiO2 NCs flexible sheets with high dielectric permittivity and low loss factor have numerous applications in light emitting and energy storage devices. In this work, polymer-based ZnO/TiO2 NCs are synthesized by co-precipitation technique. The development of various diffraction planes (X-rays diffraction analysis) related to TiO2 and ZnO phases confirms the synthesis of polycrystalline polymer-based ZnO/TiO2 NCs. The crystallinity of various phases is associated with increasing ZnO nanofillers. The surface morphology (scanning electron microscopic analysis) comprising of nanoparticles of different shapes is associated with increasing amount of nanofillers. The EDX analysis confirms the presence of Zn, O and Ti in the synthesized polymer-based ZnO/TiO2 NCs. Dielectric measurements demonstrating the sharp increase in dielectric permittivity with relatively low dissipation factor of synthesized polymer-based ZnO/TiO2 NCs are associated with increasing amount of ZnO nanofillers. The static value of dielectric constant (e’) at low frequency (100 Hz) is found to be 14.56 for sample having 10% ZnO nanofillers that is 2.11 times greater than pure PVDF and it shows relatively low value of dissipation factor. The observed σac of synthesized polymer-based ZnO/TiO2 NCs at 3.0×105 Hz and 1.0×106 Hz are ranged from 3.75-9.79 and 15.61-42.72 mS/m respectively. The decreasing complex impedance and increasing electric modulus further confirm that the synthesized polymer-based ZnO/TiO2 NCs flexible sheets are the promising candidate for better capacitive performance showing high strength and flexibility.

Tunable Dielectric Spectroscopy of PVDF Thin Films Crossbred with TiO2 Nanoparticles for the Storage Devices

“…Figure 7b shows the dissipation factor of all the PVDF‐TiO 2 NC thin films is very small compared to other dielectric measurements at the lower‐frequency range, which suggest that the PVDF‐TiO 2 NC thin films have a potential application in the piezoelectric. [ 28,31–32 ] These changes in the AC conductivity with respect to frequency and the low‐value dissipation factor suggest that the prepared NC thin films can be used in the production of energy storage devices.…”

“…Also the conduction mechanism occurring due to small polaron hopping causes an increase in AC conductivity. [28] At the higher frequency range, there is a sharp increase in the conductivity of PVDF-TiO 2 NCs thin films compared to that of PVDF thin film due to the addition of TiO 2 NPs, [7,8] which causes an increase in the mobility of charge carriers by developing the weak links in the PVDF chain and it also improves the polarity of the composite thin films and hence it shows the increase in the conductivity by increasing the conduction ways in the PVDF-TiO 2 NCs. [29,30] In the low-frequency region, the charge carriers are trapped but in the higher-frequency region the charge carriers are not trapped, due to these non-trapped charge carriers the dielectric relaxation occurs and increases the conduction in the NCs thin films.…”