Flexible interdigital in-plane supercapacitor based on laser reduced graphene oxide (LRGO)

We demonstrated and verified the use of Laser reduced graphene oxide (LRGO) supported on polyethylene terephthalate (PET) substrate for flexible supercapacitor applications. We compared the interdigitated in-plan structure with the conventionally stacked structure supercapacitor. To understand the role of increasing the number of sub-electrodes per unit area, three electrode architecture of 2, 4, and 6 sub-electrodes were studied. Polymeric gel electrolyte of poly (vinyl alcohol) and phosphoric acid (PVA-H₃PO₄) was selected for the realization of the cells. The interdigital in - plane supercapacitor with 6 sub-electrodes I-PS(6) showed a volumetric capacitance of 9.3 Fcm^-3 opposed to 3.6, 0.6, 0.5 Fcm^-3 for I-PS(4), I-PS(2), and conventional structure supercapacitor, respectively at 0.1 mA cm^-2 current density. The maximum stated energy density of 0.409 mWh.cm^-3 and power density of 994.6 W.cm^-3 were for I-PS(6). Our results clearly showed that the LRGO can hold much promise for low-cost, easy, and scalable supercapacitor fabrication.