Highly conjugated graphitic 3D carbon frameworks for supercapacitors with long cycling stability

Abstract

Bio-inspired by mussels' adhesion, a new protocol for the fabrication of large-sized carbon electrode materials (GCFs) is achieved through an adhesive self-assembly of in-situ-formed multilayered polydopamine nanospheres along with a subsequent pyrolysis. The fabricated GCFs show a 3D hierarchical porous architecture consisting of highly graphitic carbon. These features allow a rapid diffusion, high loading and effective absorbing and exchanging of charged ions in GCFs, which endows GCFs superior electrochemical performance. When tested as supercapacitor electrodes, the GCFs exhibit a high volumetric capacitance of 105 F cm−3 at a current density of 1.0 A cm−3 within a potential window of 0–1.0 V in 0.5 M Na2SO4 solution. Meanwhile, the GCFs has been assembled a simple asymmetrical supercapacitor, which can stably supply power to a LED and a small fan with an excellent cycling stability of 100% capacitance retention after 10000 charge/discharge cycles. Worthy to note, due to the versatile adhesive ability of polydopamine to almost all substrates, this developed protocol provides new avenues to fabricate large-sized core-shell electrodes, which is attractive in future portable devices.