Mycelium network inspired PVDF-HFP/g-C 3 N 4 /Mo 2 AlB 2 piezoelectric fibrous mat-based hybrid nanogenerator for underwater wireless electro-mechanical energy harvesting and battery-free aquatic rescue systems

A highly sensitive hybrid nanogenerator with a mycelium network-inspired piezoelectric mat, combined with Maxwell's displacement current, enables underwater wireless signalling for a Morse code-supported battery-free aquatic rescue system.