Laser direct writing micro-supercapacitors from graphene oxide films

摘要

This study reports the laser direct writing of graphene oxide (GO) to form reduced graphene oxide (RGO)-GO-RGO interdigitated on-chip micro-supercapacitors (MSCs) by reducing GO to RGO. The resolution of the laser writing lines can be lowered to 10 μm, which is much lower than that formed by the CO2 pulse laser, suggesting the potential to fabricate much smaller MSCs in 10 μm scale. The micro-supercapacitor employed GO itself as the humidity-sensitive electrolyte with no need of other electrolytes. The typical device shows a high capacitance of 12.5 mF/cm2 at the scan rate of 10 mV/s at the humidity of 90%, which is much higher than the reported value obtained by the pulsed CO2 laser, even the micro-supercapacitors with electrolytes.