Ferroelectric Polarization Electric Field Induced High Performance Graphene/LiNbO₃ Dynamic Diode Generator.

Abstract

Substantial endeavors have been dedicated to continuously harvesting mechanical energy from the environment, where dynamic semiconductor diode generators (DDGs) have recently been drawing significant attention as the miniature, portable in situ energy device. However, despite their unique advantages of direct-current output and high current density, the output voltage of DDG is usually less than 1 V, which needs to be further improved to satisfy the demands of practical applications. Therefore, this study proposes a vertical graphene/LiNbO₃ DDG that is conducive to an ultra-high voltage output. The coupling enhancement effect arising from the synergy between the ferroelectric polarization electric field on the LiNbO₃ surface and the built-in electric field at the graphene/LiNbO₃ interface has been identified as a key factor in achieving an impressively high open-circuit voltage output of 41.3 V and a short-circuit current of 1.53 µA. The vertical graphene/LiNbO₃ DDG can effectively power an LED without the requirement of an external energy storage and conversion circuit. Moreover, it demonstrates outstanding stability, showing no evident performance attenuation after continuous operation exceeding 3 h. The graphene/LiNbO₃ DDG has enhanced the feasibility of real-time energy supply for electronic components and paved the way for the efficient harvesting of mechanical energy from the environment.