Significantly improved dielectric and energy storage behavior of the surface functionalized CaCu3Ti4O12 nanoparticles in PVDF-CaCu3Ti4O12 nanocomposites

The effect of incorporation of amine group (-NH2) to the surface functionalized CaCu3Ti4O12 (CCT) nanoparticles in polyvinylidene fluoride (PVDF) has been studied. The thick nanocomposite films (PVDF-8FCCT and PVDF-8CCT) containing of 8 vol% loading of surface functionalized and non-functionalized CCT nanoparticles have been synthesized. The structural, dielectric and energy storage characteristics have been investigated. At 1 kHz, the dielectric constants of PVDF-8CCT and PVDF-8FCCT nanocomposite film are ~ 14 and ~ 19, respectively, whereas loss is same (~ 0.027) in both films. At moderate electric field of 500 kV/cm, the discharge energy densities of nanocomposites consisting of non-functionalized and surface functionalized CCT nanoparticles are ~ 0.8 and ~ 1.2 J/cc, respectively. The incorporation of amine group surface functionalized CCT nanoparticles in the PVDF matrix enhances the dielectric constant and discharging energy density by 35% and 50%, respectively. Improved dielectric and energy storage behavior of the PVDF-8FCCT nanocomposite thick film might be attributed to the creation of additional dipoles due to the modification of the interfaces between PVDF and functionalized CCT nanoparticles.