Improving energy storage properties of polyarylene ether nitrile with coral-like CaCu3Ti4O12 nanorods

Benefiting from the improved compatibility, rearrangement of SPEN@CCTONR and orientation of PEN, the simultaneously enhancement up to 320 % of dielectric energy storage density of PEN through the incorporating of SPEN@CCTONR and hot-stretching is achieved. [Display omitted] •Coral-like SPEN@CCTONR is fabricated via the functionalization of CCTONR with SPEN.•SPEN@CCTONR possess superior interfacial compatibility in PEN.•SPEN@CCTONR/PEN possess outstanding energy storage properties.•Dielectric performances of SPEN@CCTONR/PEN are further enhanced by hot-stretching.•Up to 320 % boosting of energy storage density is achieved. Film capacitors have attracted widespread attention in the field of power electronics due to their advantages of long service life, high-power density, rapid charging and discharging rates, operational safety, among others. Nonetheless, the persisting challenge regarding the dielectric capacitors’ insufficient energy storage density remains the primary obstacle impeding their advancement. Herein, one-dimensional (1D) coral-like calcium copper titanate (CaCu3Ti4O12) nanorod (CCTONR) is fabricated and interface modified to enhance energy storage properties of polyarylene ether nitrile (PEN). The CCTONR is fabricated through a two-step hydrothermal reaction followed by calcination, and then modified by KH550 and sulphonated PEN sequentially offering SPEN@CCTONR. Due to the 1D nature and the functionalization of SPEN on the surface of CCTONR, the compatibility and the distribution state of SPEN@CCTONR in the PEN matrix are conspicuously improved. Furthermore, a secondary dispersion of SPEN@CCTONR is achieved in the SPEN@CCTONR/PEN composite via uniaxial hot-stretching. As a result, the dielectric permittivity is increased to 17.96, while the breakdown strength remains 199.4 kV/mm for the stretched SPEN@CCTONR/PEN film with filler content of 15 wt%. Correspondingly, an energy storage density of 3.16 J/cm3, with an boosting of 320 % in comparing with that of PEN, is achieved. This stretched SPEN@CCTONR/PEN film with leaped energy storage density would be a promising candidate for future flexible dielectric materials.