Constructing Highly Conductive Porous/Honeycomb Networks on Core–Shell Nanoarrays for Flexible Asymmetric Supercapacitors with Superior Performance

Abstract Metal nanoelectrode materials often struggle to combine ultrahigh capacitance, rate capability, and cycling stability in flexible supercapacitors. This work addresses this by constructing a continuous, highly conductive porous/honeycomb carbon network on carbon cloth‐supported core–shell nanoarrays using graphite‐like crystalline nanomaterials (GCNs). The positive electrode is an amorphous NiCo x S y @NiCo 2 S 4 nanorod array (NCS‐7), while the negative electrode features a microcrystalline Fe 2 O 3 @Fe 2 O 3 open dendritic nanoarray (Fe 2 O 3 ‐800). The porous/honeycomb network derived from two‐layer GCNs coating combines high conductivity, mesoporous structure, and strong interfacial coupling. The resulting 2GCNs@NCS‐7 and 2GCNs@Fe 2 O 3 ‐800 electrodes exhibit ultrahigh specific capacitance of 3168 and 1026 F g −1 , retain over 90% capacitance at 20 A g −1 , and maintain >92% capacity after 20 000 cycles at 10 A g −1 . DFT calculations confirm that GCNs induce a metallic transition in the electronic structure and strengthen interfacial bonding, facilitating electron transport and OH − adsorption. The assembled 2GCNs@NCS‐7//2GCNs@Fe 2 O 3 ‐800 flexible asymmetric supercapacitor achieves high energy densities of 112.2 Wh kg −1 (852.5 W kg −1 ) and 95.1 Wh kg −1 (15 700 W kg −1 ), with a high capacitance retention of 91.66% after 20 000 cycles. This study provides a novel strategy for rationally constructing high‐quality metallic nanoelectrodes for advanced flexible energy storage.