A 3D Heterostructural Composite Comprising MOF-Derived Ni(OH)2 and NiAl LDH on rGO for Supercapacitors

Abstract

The development of high-performance cathode materials through rational heterointerface engineering remains pivotal for advancing hybrid supercapacitors (HSCs) technologies. Here, we construct a three-dimensional ternary heterostructure composite Ni(OH)₂/NiAl LDH/rGO (N-OH/NA/rG) by sequential integration of metal-organic frameworks (MOF)-derived Ni(OH)₂, NiAl LDH and reduced graphene oxide (rGO). The covalent anchoring of NiAl LDH nanosheets on oxygen-functionalized rGO substrates mitigates restacking issues, establishing a conductive network with enhanced charge transfer kinetics. The alkaline etching of Ni-MOF precursors preserves their hierarchical porosity while converting to pseudocapacitive Ni(OH)₂. Synergistic effects among components yield increased active site density, dual charge storage mechanisms, and optimized ion diffusion pathways. The optimized composite achieves a high specific capacitance of 1481.7 F/g at 1A/g, along with excellent rate capability and cycle performance, establishing a new paradigm for designing multi-component heterostructure electrodes through MOF-derived interface engineering. Furthermore, the N-OH/NA/rG//AC HSC device demonstrates a high power density and energy density, coupled with long-term cycle stability, underscoring the substantial potential of N-OH/NA/rG as a cathode material for HSCs.