In this study, we report the facile synthesis of reduced graphene oxide/vanadium pentoxide (GV) composites and the application of this material towards the supercapacitor application. The as-fabricated reduced graphene oxide/vanadium pentoxide (GV-3) composite electrodes displayed outstanding electrochemical performance with a maximum specific capacitance of 250 F g−1 at 5 mV s−1 and excellent cycling stability, retaining 95 % of the initial capacitance, even after 5000 cycles, which shows improved behavior compared to rGO and V2O5. Further, the synthesis process is simple, less time consuming, and requires no sophisticated instruments. In addition, we have demonstrated a self-powered photosensor system by integrating the solid-state symmetric GV supercapacitor device with a nanogenerator and photosensor. These results indicate that the reduced graphene oxide/vanadium pentoxide composite electrode can be useful for improved high-performance supercapacitors.