Designing a high-performance electrode material for hybrid supercapacitor: 1D–2D NiCo carbonate hydroxide nanofiber interlinked microsheet architecture

Developing simple nanoarchitecture and exploiting distinctive components are the two most significant strategies for advancing high-performance electrode materials for hybrid supercapacitors (HSCs). However, severe agglomeration and inability to maintain a stable structure or design of nanomaterials are unfavorable to the procurement of electrochemical devices with exceptional efficiency. Herein, a facile approach was demonstrated for designing and synthesizing NiCo carbonate hydroxide (NCCH) nanoarchitecture by a hydrothermal method. The relative amounts of Ni/Co have been shown to significantly impact the physicochemical and electrochemical properties of the resulting materials. In particular, the material with a Ni/Co proportion of 2:1 (NCCH1) exhibits a linked architecture of 1D nanofiber and 2D microsheet. This nanoarchitecture offers numerous advantages, including offering additional active sites for redox reactions, shortening electron/ion transport paths, and alleviating the volume change during cycling. The optimized NCCH1 electrode exhibits a superior specific capacitance of 2408 F g⁻¹ at a specific current of 1 A g⁻¹, with excellent rate performance. Furthermore, the fabricated HSC attains a striking specific energy of 50.1 Wh kg⁻¹ at a specific power of 805.6 W kg⁻¹ while maintaining prominent cycling stability. Impressively, these findings suggest that the NCCH1 has excellent potential as a capable candidate for the fabrication of high-performance energy storage devices.