Carbon-anchored Sb nanoparticles as high-capacity and stable anode for aqueous alkaline batteries

Abstract

Antimony (Sb) holds a high theoretic capacity and suitable redox potential as a promising anode for aqueous alkaline batteries (AABs). However, the uncontrollable nucleation for SbO₂⁻ and promiscuous water-induced side reactions severely degrade the reversibility of Sb anode. Herein, the carbon-anchored Sb nanoparticles are constructed to induce uniform Sb plating/stripping for high-performance AABs. The experimental results reveal that the enhanced interaction between carbon and antimony as well as defective carbon can significantly improve the electrical conductivity and decrease the Sb nucleation overpotential. Accordingly, the as-prepared Sb anode enables preferential plating of Sb rather than parasitic side reactions. As a result, the cycle life of A-Sb/CF is sustained over 500 cycles at 10 mA cm⁻²/2 mAh cm⁻². Even at the high capacity of 4 mAh cm⁻², this anode can cycle stably for 225 cycles, which is significantly better than the Sb/CF counterpart. Furthermore, the assembled Ni₃S₂@Ni(OH)₂//A-Sb/CF full battery demonstrates a high capacity of 2.17 mAh cm⁻² and a stable cycle life of over 500 cycles.