Spacing graphene and Ni-Co layered double hydroxides with polypyrrole for high-performance supercapacitors

The urgent need of high-performance of energy storage devices triggers us to design newly class of materials. Generally, the materials feature with high conductivity, abundant pores and excellent stability. Here, a sandwiched hybrid composite containing reduced graphene oxide, polypyrrole and Ni-Co layered double hydroxides (RGO/PPy/NiCo-LDH) was prepared in a facile way. The polypyrrole was incorporated in the two dimensional (2D) nanosheets, which not only serve as the spacer to increase the surface area, but also enhance the conductivity of the nanocomposite. The obtained architecture was employed as an advanced electrode in a supercapacitor. The electrode shows an ultrahigh specific capacitance (2534 F g(-1) at 1 A g(-1)) and good cycling efficiency (78 % after 5000 cycles). Moreover, an asymmetric cell based RGO/PPy/NiCo-LDH composite demonstrates excellent electrochemical properties and good prospect of practical use. (C) 2020 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.