The MnAl-alloy nanoparticles incorporated PVDF-based piezoelectric nanogenerator as a self-powered real-time pedometer sensor

This study introduces a flexible, sensitive, and cost-effective hybrid piezoelectric nanogenerator (PENG) by integrating MnAl-alloy nanoparticles into a poly (vinylidene fluoride) (PVDF) nanocomposite film. The MnAl-alloy nanoparticles serve as a nucleating agent for promoting the formation of the electroactive β-phase. It is observed that the electroactive β-phase, dielectric permittivity, saturation polarization, and output performance of the device improve with the incorporation of the MnAl-alloy nanoparticles up to 7.5 wt. % in the PVDF matrix. Hence, in this work, we report a MnAl-alloy-based optimized piezoelectric nanogenerator device using a free-standing nanofiber mat (7.5 wt. % MnAl-alloy) prepared by the electrospinning technique. The as-fabricated piezoelectric nanogenerator effectively channels charges generated by mechanical stress to the electrodes, resulting in an impressive output voltage of approximately 16 V and an output current of around 7.1 μA, yielding a power of 47 μW across 4.5 MΩ resistor. Furthermore, energy harvesting from human movements such as jogging, knee bending, and walking is demonstrated for practical application. A piezo potential of approximately 8 V generated during walking showcases the development of a self-powered pedometer. Furthermore, tapping the PENG charges a capacitor of 0.1 μF up to approximately 1 V, demonstrating the potential application for the power up of small portable electronic devices.