Laser engraving and punching of graphene films as flexible all-solid-state planar micro-supercapacitor electrodes

Abstract

The design of lightweight and flexible micro-supercapacitors (MSCs) to couple with the unprecedented boom of microelectronics is extremely desirable but remains challenging. Herein, a facile and straightforward laser engraving and punching strategy has been reported to fabricate graphene-based planar MSCs with outstanding flexibility, superior modularization and programmable pore generation. The resulting planar flexible MSCs are free of external metal current collectors and separators, and exhibit high specific capacitance, outstanding rate capability and robust stability with 98.4% capacitance retention even after 25,000 cycles in the PVA/H2SO4 gel electrolyte. Notably, the output voltage and capacitance of our prepared MSCs are readily adjustable through simple serial and parallel connection, indicative of superior modularization and performance uniformity.