Multicore–shell bismuth nanoparticles@N-doped porous carbon nanorods for dendrite-free zinc metal anodes

Aqueous zinc (Zn)-based batteries with high cyclic stability, exceptional safety, and low cost hold great promise as next-generation energy storage devices. However, Zn metal anode suffers from serious dendrite growth, hydrogen evolution, and Zn corrosion during plating/stripping cycles, hampering its practical utilization. Herein, we report a multicore–shell structure of bismuth (Bi) nanoparticles embedded within N-doped porous carbon nanorods (NPCN) (Bi@NPCN) to regulate Zn deposition behavior. Theoretical simulation and in situ optical microscopy revealed that the abundant Bi nanoparticles with high zincophilic property strongly adsorbed Zn²⁺, enabling rapid and massive Zn deposition. Meanwhile, NPCN with porous feature provides sufficient space for accommodating Zn volume expansion. Electrochemical tests demonstrated an ultra-stable dendrite-free Zn deposition behavior for 1500 h, high rate capability up to 20 mA·cm⁻², and an exceptional Coulombic efficiency of ~ 100% after 1200 cycles. The Zn-ion batteries coupled with ammonium vanadate cathode exhibit a highly-stable cyclic performance for 3000 cycles at 5.0 A·g⁻¹, with a high capacity retention of 66.7%. Impressively, a remarkable long-term cyclic performance over 10,000 cycles was realized when employing active carbon cathode. This study offers a new strategy of utilizing multicore–shell structure with zincophilic seeds to achieve dendrite-free Zn metal anode.