Impact of Current Collector on Supercapacitive Performance of Hydrothermally Reduced Graphene Oxide Electrode
Nidhi Tiwari, Shrinivas Kulkarni
Abstract
The current collector base used for the deposition of active materials is the backbone of all electrochemical/supercapacitive energy storage systems. In this work, reduced graphene oxide (RGO) is synthesized by using the modified Hummers method followed by facile hydrothermal deposition of RGO on two different current collector bases namely carbon cloth and nickel foam. The resulting RGO electrodes are characterized by structural, morphological, and electrochemical methods. Morphological studies reveal that RGO grown on carbon cloth shows the formation of connected microspheres whereas RGO on nickel foam exhibits nanosheets-like architecture. In brief, RGO microspheres retain a specific capacitance of 578.56 F/g at a scan rate of 5 mV/sec, whereas RGO nanosheets show a specific capacitance of 249.31 F/g at the same scan rate. Also, RGO electrodes display long-term cyclic stability with capacitance retention of up to 800 cycles. The results recommend that RGO grown on nickel foam has enhanced electrochemical performance compared to that on carbon cloth. The present work provides a better insight into understanding and selecting an appropriate current collector base depending on the synthesis method and application area of RGO electrodes.