Thick piezoelectric films by aerosol deposition at room temperature: corona poling and force sensing

In this study, we employed corona poling to improve the piezoelectric properties of as-deposited BaTiO3 films and conducted a vibration energy harvesting test. Dielectric measurements indicated that the dielectric constant of the as-deposited film increased with temperature, and the frequency dependence of the dielectric constant was minimal at room temperature. Applying an electric field of 1500 kV cm−1 resulted in a recoverable energy density of 7.1 J cm−3 and an energy storage efficiency of 54%. The corona polarization treatment could align dipoles under high electric fields and prevent dielectric breakdown owing to local defects created by the aerosol deposition (AD) process. The vibration test yielded a harvested energy of 172 nJ and an output voltage of 2.67 V, which is suitable for force sensor applications. Polarization via corona discharge is also feasible without an electrode. Integrating AD with corona poling may benefit new capacitors, sensors, and energy harvesting technologies.