Construction of three-dimensional (3D) vertical nanosheets electrode with electrochemical capacity applied to microsupercapattery

Abstract

The preparation of heterostructure composites is regarded as an effective measure to enhance the electrochemical performances of pure component materials for energy conversion and storage. This paper reports a rapid microwave process to synthesize novel hierarchical multi-walled carbon nano-tubes and graphene nano-ribbons/Co–Ni LDH (MWGR/Co–Ni LDH) composites with superior performances in supercapattery. MWCNTs-GONRs with high conductivity, structural stability and electrochemical properties, and LDH with the construction of p-n junction are also profitable to transpire redox reaction. Thus, MWGR/Co–Ni LDH exhibites the distinctive heterostructure and splendid electrochemical properties (a high specific capacitance of 1030.2 C g−1 at 1 A g−1). In addition, the as-prepared MWGR/Co–Ni LDH//AC device performs the maximum energy density of 47.2 Wh kg−1 at power density of 0.85 kW kg−1 and good cycling performance of 88.8% retention after 10,000 cycles at 10 A g−1. Furthermore, the assembled asymmetric supercapattery (ACS) is adequate to provide energy for multiple lights emitting diodes (LEDs), which holds great promising practical applications for supercapattery.