Enhanced Al-Storage Performance by Electronic Properties Optimization and Structural Customization in MOF-Derived Heterostructure

Chalcogenide cathodes with multi-electron transfer characteristics are indispensable to aluminum-ion batteries (AIBs). Nevertheless, their grievous capacity degradation and sluggish reaction kinetics remain fundamental challenges for the practical application. Herein, a Cu2S/Ni3S2 multiphase structure within the metal-organic frame (MOF) derived carbon decoration layer (CNS@MC) is constructed to elevate the intrinsic electronic properties of chalcogenide cathode and realize high-performance AIBs. The existence of outer carbon layer and strong orbital interaction at inner heterointerfaces eliminates the bandgap and arises more electrons at Fermi level, efficiently reducing the energy barrier for electron transfer and achieving high reactivity within cathodes. The CNS@MC also presents a strong electronic interaction with active solvent groups, which is beneficial to capture Al3+ and facilitate the three-electron charge-storage reactions. Experimental results demonstrate that the tailored CNS@MC cathode possesses superior redox kinetics due to the sufficient surface area and rapid Al-ion diffusion during cycling. Meanwhile, the robust CNS@MC delivers ultra-high electrochemical stability (131.1 mAh g-1 over 3500 cycles) with high coulombic efficiency and outstanding rate performance. This work offers new opportunities for optimizing the intrinsic properties of the chalcogenide electrodes based on MOF derivatives and heterostructure, providing novel thoughts for designing high-performance AIBs. A metal-organic frame derived heterostructure Cu2S/Ni3S2@MOF-derived C is proposed to achieve high-performance chalcogenide cathode. This work provides a comprehensive exploration, including electronic properties, electrochemical performance, operating mechanism, and electronic interactive information between electrode and electrolyte solvent groups.image