Enhanced electrochemical performance of three-dimensional graphene/carbon nanotube composite for supercapacitor application

In this work, we developed a facile route to synthesize three-dimensional graphene/carbon nanotube (3DG/CNT) hybrids as electrodes for binder-free electrical double layer capacitor (EDLC) by using chemical vapor deposition (CVD) method. The 3DG/CNT composites have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). It was found that the 3DG/CNT with interconnected architecture exhibit improved capacitive characteristic and electrical conductivity compared to that of pure 3DG. The 3DG/CNT composites have high specific capacitance of 197.2 F/g and excellent capacity retention rate of 93% after 1000 cycles. The experiment results show that the as-synthesized 3DG/CNT hold great potential as candidate as electrode for binder-free EDLC. (C) 2019 Elsevier B.V. All rights reserved.