3D channeled porous carbon hosts with cobalt nanoparticle-induced zincophilicity for stable zinc anodes

초록

Aqueous zinc-ion batteries (ZIBs) have seen substantial progress, motivated by the increasing emphasis on environmentally benign and intrinsically safe energy storage solutions. However, Zn dendrite formation remains a significant challenge, leading to rapid capacity decay, low Coulombic efficiency (CE), and internal short circuits. Herein, we present three-dimensional (3D) channeled-porous carbon particles decorated with Co nano-particles (CPC-Co) as a highly reversible Zn host to address these challenges. The incorporation of zincophilic Co nanoparticles effectively reduces the nucleation overpotential, promoting uniform Zn deposition, while the 3D channeled-porous carbon framework accommodates volume changes during Zn plating/stripping. As a result, the CPC-Co electrode enables stable Zn plating/stripping for over 830 cycles at 2 mA cm-2, with an average CE of 99.1%. Even at higher current densities of 6 and 10 mA cm-2, the electrode maintains extended cycling stability for 635 and 100 cycles, respectively. Density functional theory calculations further suggest that the Co nano-particles act as effective zincophilic sites for achieving consistent Zn nucleation. Consequently, a full cell incorporating the Zn@CPC-Co anode and V2O5 cathode exhibits excellent cycling stability over 6000 cycles at 1 Ag-1.

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