Hybrid carbon framework of graphitic carbon and bamboo-like CNTs for stable lithium-metal anodes

초록

Stable and high-performance Li metal anodes (LMAs) are essential for the advancement of next-generation energy storage systems. Constructing a three-dimensional carbon host that guides uniform Li deposition is an effective approach for suppressing dendrite growth and mitigating volume fluctuations during cycling. In this study, a carbon microsphere framework comprising graphitic carbon regions and moderately grown bamboo-like carbon nanotubes (b-CNTs) is synthesized using dextrin, dicyandiamide, and iron nitrate precursors via a spraydrying process, followed by controlled heat treatment. The resulting hybrid exhibits a well-balanced architecture that harmonizes the lithiophilicity, electronic conductivity, and interfacial stability. Electrochemical evaluations further verify its superior performance, with asymmetric cells maintaining a Coulombic efficiency above 98.0% for over 230 cycles, and symmetric cells exhibiting stable voltage hysteresis of approximately 25 mV for more than 3800 h without short-circuit failure, demonstrating robust electrochemical performance during repeated Li deposition and stripping. Furthermore, full cells paired with LiFePO4 cathodes deliver high reversible capacities and outstanding rate retentions, highlighting the superior ion transport and interfacial robustness of the optimized host. These findings indicate that a hybrid carbon framework integrating graphitic carbon regions and moderately developed b-CNTs provides a practical and scalable design for durable, high-performance LMAs for next-generation rechargeable batteries.

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