The aim of the current work is to d

The aim of the current work is to develop novel nanocomposites of a ceramic matrix with polymer fillers using the cold sintering process for the development of high energy density capacitors for various technological applications in the field of electronics, space, healthcare, etc. In the past decade, perovskite-based ceramics and composites showedvery promising energy densities such as 0.7BaTiO3–0.3BiScO3 (6.1 J/cm3),22 Mn doped 0.8CaTiO3–0.2CaHfO3 (4 J/cm3),CaZr0.80Ti0.20O3 (4 J/cm3),24 etc. Recently, sodium niobate (NaNbO3) attracted the attention of researchers owing to its interesting structural and intermittent ferroelectric behavior.25–28 NaNbO3 can exhibit seven different crystalline phases, namely, N, P, R, S, T1, T2, and U.25,26 Depending on the phase, this material changes its behavior from ferroelectric, to anti-ferroelectric or paraelectric. The transition from the P-R phase generally occurs at 360-370℃.Although many polymers such as polypropylene, polycarbonate, polyamide, polyester, aromatic polythiourea, aromatic polyurea,polyvinylidene-fluoride (PVDF), and their related composites have been reported, ferroelectric PVDF was selected in the present work since it possess higher permittivity. PVDF exhibits four different polymorphic phases, α, β, γ, and δ. Among these phases, α is a non-polar phase, β is piezoelectric, γ is ferroelectric but hardly accessible, and δ is the polar version of α-PVDF.34 Different polymorphs can be stabilized through different methods leading to interesting properties making PVDF desirable for such applications.