A ZIF-derived ZnS@Co 3 S 4 coupled with MXene and Ni-LDH on Ni foam: constructing a honeycomb-like electrode for advanced supercapacitor

Abstract Zeolite imidazolate framework (ZIF)-derived bimetallic sulfides and layered double hydroxides (LDHs) have emerged as promising electrode materials for supercapacitors, owing to their porous layered structures, high electrochemical activity, tunable molecular architectures, low cost, and high specific capacitance. In this study, a unique composite material comprising ZIF-derived ZnCo bimetallic sulfide and LDH with a honeycomb-like structure was in situ grown on nickel foil (NF) via a controlled self-sacrificial template strategy. In contrast to previous reports, the resulting ZnS@Co 3 S 4 @MXene@Ni-LDH/NF composite integrates the advantages of MXene, LDH, and sulfides, leading to significantly enhanced conductivity, structural stability, and catalytic activity. The ZnS@Co 3 S 4 @MXene@Ni-LDH/NF electrode exhibits a uniform network structure with a thickness of approximately 1 µ m coated on NF, and delivers a high specific capacitance of 1356.1 F·g −1 at a current density of 2 A·g −1 . Furthermore, an asymmetric supercapacitor assembled with ZnS@Co 3 S 4 @MXene@Ni-LDH/NF as the positive electrode and activated carbon as the negative electrode achieves a high energy density of 34.08 Wh·kg −1 and a power density of 742.3 W·kg −1 at 1 A·g −1 . This device successfully powers LED lights for 5 min, demonstrating its practical applicability. These results underscore the outstanding electrochemical performance of the ZnS@Co 3 S 4 @MXene@Ni-LDH/NF electrode, highlighting its potential for applications in supercapacitors and related energy storage fields.