Lotus-Root-Like Carbon Fibers Embedded with Ni-Co Nanoparticles for Dendrite-Free Lithium Metal Anodes.

Chen, Chen; Guan, Jun; Li, Nian Wu; Lu, Yue; Luan, Deyan; Zhang, Cai Hong; Cheng, Guang; Yu, Le et al. · Adv Mater · 2021

basic_science · Level V

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Abstract

The growth of lithium (Li) dendrites and the huge volume change are the critical issues for the practical applications of Li-metal anodes. In this work, a spatial control strategy is proposed to address the above challenges using lotus-root-like Ni-Co hollow prisms@carbon fibers (NCH@CFs) as the host. The homogeneously distributed bimetallic Ni-Co particles on the N-doped carbon fibers serve as nucleation sites to effectively reduce the overpotential for Li nucleation. Furthermore, the 3D conductive network can alter the electric field. More importantly, the hierarchical lotus-root-like hollow fibers provide sufficient void space to withstand the volume expansion during Li deposition. These structural features guide the uniform Li nucleation and non-dendritic growth. As a result, the NCH@CFs host enables a very stable Li metal anode with a low voltage hysteresis during repeated Li plating/stripping for 1200 h at a current density of 1 mA cm<sup>-2</sup> .