Nanocellulose‐Induced “Surface‐Lock” Engineering: Curbing the Dissolution of MnO ₂ for High‐Performance Zn–MnO ₂ Flexible Electrodes

ABSTRACT Carbon‐based substrates in Zn–MnO 2 flexible batteries have issues of low adhesion to MnO 2 , impacting cycle stability and capacity performance. A triple‐synergistic strategy integrating C–O–Mn covalent bonding, wettability optimization, and hierarchical mesoporous engineering via cellulose nanofibers/carbon nanotube (CNF/CNT)‐modified carbon cloth (CC) was proposed. This design achieves a “surface‐locking” effect between the substrate and electrode materials, which was proven through theory and experiments. Density functional theory (DFT) simulations validate the “surface‐locking” mechanism, where oxygen functionalities on CNF can form robust CO–Mn bonds with MnO 2 , inducing an increase in MnO 2 adsorption energy from −0.21 eV (pristine CC) to −1.36 eV, effectively suppressing Mn dissolution. Optimal wettability (contact angle: 97°) reduced Zn 2+ desolvation and water‐induced side reactions. Hierarchical pore structures accelerated Zn 2+ diffusion. The optimized CC@CNF 1 /CNT 2 –MnO 2 cathode achieves 92% capacity retention after 2000 cycles at 1 A/g. This study highlights a surface engineering strategy that effectively addresses the individual challenges associated with interfacial adhesion, reaction kinetics, and ion transport. This strategy offers fundamental insights into electrode interface modification for the development of next‐generation flexible energy storage systems.