Fast preparation of vertical graphene nanosheets by helicon wave plasma chemical vapor deposition and its electrochemical performance

Abstract

We investigated the growth process of vertically-oriented graphene nanosheets (VGs) on a Si substrate by helicon wave plasma chemical vapor deposition (HWP-CVD). The results show that VGs has good vertical orientation on Si and the growth process does not require the catalyst. Modulation of height, thickness and mesh size of vertical graphene nanosheets can be achieved by changing the growth time. It is found that the height of VGs is linear with time. Extremely high growth rate, approximately 0.26 μm/min, is achieved, in contrast to previous studies. The results of Cyclic voltammetry (CV) measurement indicating that VGs have a very rapid current–voltage response, an excellent electrochemical reversibility and excellent capacitive behavior. The VGs was able to deliver an outstanding specific capacitance value of 345 μF/cm2, and demonstrated an excellent rate capability, which retained 94.41%.