Hydrated metal salt and Y3Fe5O12–Na0.5K0.5NbO3-incorporated P(VDF-HFP) films: a promising combination of materials with multiferroic and energy harvesting properties.

The composite approach is very effective in developing multiferroic systems with remarkable magnetoelectric coupling coefficients. In this work, P(VDF-HFP)-based films containing 2, 4, 8 and 16 wt% Y₃Fe₅O₁₂–Na_0.5K_0.5NbO₃ nanocrystalline particles were developed via a simple solvent cast process. In order to facilitate the β-phase crystallization of the P(VDF-HFP), hydrated ferric nitrate was utilized during the preparation of the films, which resulted in significant improvement in the β-phase content. Moreover, the use of Y₃Fe₅O₁₂–Na_0.5K_0.5NbO₃ also triggered the β-phase crystallization of the P(VDF-HFP). At the highest filler loading of 16 wt%, a magnetoelectric coefficient of 33.6 mV cm⁻¹ Oe⁻¹ was achieved. Piezoelectric energy harvesting studies were also carried out using the composite film containing 16 wt% Y₃Fe₅O₁₂–Na_0.5K_0.5NbO₃ nanocrystalline particles. A maximum open-circuit voltage of 3.79 V was measured when a compressive force of 5 N was applied to the energy harvesting device. [ABSTRACT FROM AUTHOR]