Flexible Pillared Graphene‐Paper Electrodes for High‐Performance Electrochemical Supercapacitors

Abstract Flexible graphene paper (GP) pillared by carbon black (CB) nanoparticles using a simple vacuum filtration method is developed as a high‐performance electrode material for supercapacitors. Through the introduction of CB nanoparticles as spacers, the self‐restacking of graphene sheets during the filtration process is mitigated to a great extent. The pillared GP‐based supercapacitors exhibit excellent electrochemical performances and cyclic stabilities compared with GP without the addition of CB nanoparticles. At a scan rate of 10 mV s −1 , the specific capacitance of the pillared GP is 138 F g −1 and 83.2 F g −1 with negligible 3.85% and 4.35% capacitance degradation after 2000 cycles in aqueous and organic electrolytes, respectively. At an extremely fast scan rate of 500 mV s −1 , the specific capacitance can reach 80 F g −1 in aqueous electrolyte. No binder is needed for assembling the supercapacitor cells and the pillared GP itself may serve as a current collector due to its intrinsic high electrical conductivity. The pillared GP has great potential in the development of promising flexible and ultralight‐weight supercapacitors for electrochemical energy storage.