Electron Highways Meet Nanoconfined Reactors: Building Ultradurable Flexible Supercapacitors Through Synergistic Transport‐Structure Manipulation of NiCo‐LDH‐Supported MXene

Abstract Nickel‐cobalt layered double hydroxides (NiCo‐LDHs) are considered highly promising electrode materials for supercapacitors (SCs). Nevertheless, their limited conductivity and inherent stacking defects lead to inactive electronic states, thereby constraining their electrochemical performance. Here, a dual‐conductive‐engineered flexible electrode is fabricated through synergistic integration of in situ constructed 3D porous LDH with Ti 3 C 2 T x nanosheets deposition, establishing a semi‐confined reaction microenvironment. The collaborative conductive architecture and confinement‐enhanced effects enable continuous modulation of Faradaic reaction kinetics during charge/discharge processes, achieving breakthrough improvements in both energy density and cycling stability. The optimized Ti 3 C 2 T x /LDH/CC‐50 electrode delivers a remarkable specific capacitance of 1598.7 F g⁻¹ at 1 A g⁻¹, along with excellent rate performance of 87.2% (10 A g −1 ). Furthermore, the constructed aqueous asymmetric supercapacitor (ASC) delivers an impressive energy density of 72.4 Wh kg − ¹ and remarkable cycling stability (90.5% retention after 10 000 cycles). A flexible solid‐state asymmetric SC (FSASC) is also fabricated, showcasing a significant energy density of 83.9 Wh kg − ¹ at 900 W kg − ¹ with excellent mechanical flexibility. DFT simulations further revealed enhanced electron transport and a greater number of active sites due to the reduced energy barrier. This work contributes new insights into the structural design of LDH/MXene nanohybrid electrodes for advanced energy density supercapacitors.