Dual-Function Layered Double Hydroxide Simultaneously Serving as Metal Source and Template to Guide Oriented Metal–Organic Framework In Situ Growth for High-Performance Flexible Supercapacitor Electrodes

The accelerated progression of portable and wearable electronics has given rise to a substantial demand for flexible electrode materials that exhibit exceptional electrochemical performance. Herein, we propose an interfacial engineering strategy to construct NiMn-layered double hydroxide@metal–organic framework (NiMn-LDH@MOF) heterostructures on carbon cloth via an integrated electrodeposition-hydrothermal in situ conversion approach. The LDH phase simultaneously serves as both a metal source and structural template, enabling oriented MOF growth through coordination with 1,3,5-benzene tricarboxylic acid ligands. This heterostructure integrates abundant active sites, efficient electron transport pathways, and enhanced redox activity, collectively boosting electrochemical performance. Density functional theory calculations have been used to verify that the heterostructure significantly reduces the bandgap and enhances the adsorption energy for OH –, thus improving the reaction kinetics. The electrode delivers 1432 F g –1 at 0.5 A g –1, retaining 84.11% capacity after 5000 cycles. Ex situ characterization elucidates the charge storage mechanism and structural evolution during cycling. A flexible asymmetric solid-state supercapacitor assembled with this electrode delivers 298 F g –1 at 0.5 A g –1 and 105.9 Wh kg –1 at 399 W kg –1 . This work highlights the synergistic effects between LDH and MOF in heterostructures, offering a novel strategy for developing high-performance supercapacitors.