Novel Integrated Tandem-Interdigitated Performance-Enhancing Flexible Planar Microsupercapacitors Based on Graphene Quantum Dots

Boosting requirements for portable and wearable electronic systems have substantially stimulated sustainable advancement of high-performance flexible planar microsupercapacitors (MSCs). However, the low comprehensive electrochemical performance of flexible planar MSCs proves to be the major hurdle to practicality. Herein, the scalable manufacturing of integrated flexible planar MSCs based on graphene quantum dots (GQDs) with tandem-interdigitated architecture was demonstrated through modified liquid–air interfacial self-assembly and photolithography methods. These flexible planar MSCs exhibit exceptional overall electrochemical performance with an areal specific capacitance of 6.35 mF cm−2, areal energy density of 3.53 μWh cm−2, areal power density of 8.10 mW cm−2, excellent cyclic stability maintaining 93.61% of their initial capacitance following 10,000 cycles of cyclic voltammetry operations, and outstanding mechanical flexibility, which attributes to the synergistic effects of GQD active materials, tandem-interdigitated microelectrodes and bendable flexible polyethylene terephthalate substrate. This work unveils a straightforward and scalable process for fabricating high power density, all-solid-state, and integrated flexible planar MSCs with rapid frequency response. Considering their practical utility, these devices hold significant promise as on-chip micro-power sources for portable electronics and wearable microsystems.