Hierarchical micro-nano structure based NiCoAl-LDH nanosheets reinforced by NiCo2S4 on carbon cloth for asymmetric supercapacitor

Rational construction of microstructure and successful incorporation of multiple components offer a scalable strategy for applying electrode materials in asymmetric supercapacitors. Herein, a hierarchical hybrid structure of NiCoAl-layered double hydroxide (NCA-LDH) and ternary spinel NiCo2S4 (NCS) on carbon cloth (CC) without binders is obtained through three-step hydrothermal reaction. The [email protected]@CC electrode exhibits outstanding electrochemical performance with 1775F g−1 at 1 A g−1. Its capacitance retention is 79.6% when cycles reach 10 000 under 10 A g−1, benefiting from the hierarchical hybrid structure and improved overall conductivity. A flexible solid-state asymmetric supercapacitor (FSASC) is assembled using [email protected]@CC and activated carbon coated on carbon cloth ([email protected]) for positive and negative electrodes, respectively. It possesses 33.13 Wh kg−1 under 750 W kg−1, and also maintains a better cycling performance of 71.4% at 1 A g−1 after 10 000 cycles. Hierarchical hybrid [email protected]@CC electrode provides a favorable and scalable candidate for the development of FSASC device with superior performance.