Binder-less MnO2 nanosheets as energy storage electrode for the piezoelectric mediated self-charging electrochemical supercapacitor

Integrated energy systems are of great interest as it couples the both the energy harnessing and storage onto a single sustainable component for the practical IoT applications. In this work, we demonstrated the integration of energy storage and harnessing in a single component system which can be charged via bio-mechanical force. The integrated self-charging supercapacitor (ISCS) is fabricated with the aid of electrochemically deposited MnO₂ and ionogelled electrospun PVDF nanofibrous mat as piezoelectric separator. The self-charging characteristics of the MnO₂/CC ISCS is studied under various applied force with the highest charging voltage of 490 mV. The self-charging mechanism of the MnO₂/CC ISCS is explained via piezoelectrochemical phenomenon. This study highlights the usage of binder free electrode for the self-charging supercapacitor which will enhance the energy conversion and storage process over the binder-based devices. Overall, the results provide a new insight in fabrication of binder free electrodes, which might lead to enhanced performance considering the state of the art of self-charging supercapacitors.