Improvement of the electroactive β -phase nucleation and piezoelectric properties of PVDF-HFP thin films influenced by TiO2 nanoparticles

A piezoelectric nanocomposite film is designed to convert daily human activities and acoustic vibrations into usable electrical energy. The nanoparticles (NPs) of titanium dioxide (TiO2) act as a nucleating agent within the PVDF-HFP matrix, which improves the overall performance of the piezoelectric nanocomposite film. They have effectively improved the piezoelectric properties of the β phase of the PVDF-HFP nanocomposite films. In this work, a high-performance piezoelectric material is presented which can be used as an autonomous system. Titanium dioxide nanoparticles (TiO2 NPs)/PVDF-HFP composites were prepared by solution casting method in Dimethyl Acetamide (DMAc) solvent with various contents of TiO2. The compatibility between the PVDF-HFP matrix and TiO2 nanoparticles results in the formation of purely piezoelectric β-polymorph at 1 wt% of TiO2 content. Bellow that content a mixture of β and α-polymorph is observed. The as-obtained flexible nanocomposite films with such TiO2 nanoparticles content can be used as active materials in the field of piezoelectric applications. The crystallinity phases of the PVDF-HFP thin film composites and the β-polymorph formation were characterized by Fourier transform infrared spectroscopy.