Higher mechanical stability and mutual-stabilizing/confining effect enables anti-pulverization SbSn alloy/N-doped porous carbon with high-performance in sodium-based dual-ion batteries

Alloy-based materials with suitable operating potential and remarkable theoretical specific capacity have captured rising attention in sodium-ion energy storage devices. However, their giant volumetric effect is generally susceptible to irreparable crack and pulverization, ultimately leading to electrode failure. Herein, a hybrid of SbSn alloy nanoparticles implanted in honeycomb-like N-doped porous carbon (SbSn/NPC) is delicately designed through in-situ self-template-assisted pyrolysis method. In such a configuration, the “mutual-stabilizing/confining” behavior of SbSn during Na+ storage can effectively offset partial volume effects and cushion the overall stress, and the NPC can produce dozens of edges/defects for Na+ adsorption and significantly alleviate particle agglomeration. Theoretical calculation combined with structural evolution analysis further demonstrate that the SbSn/NPC electrode exhibits remarkable mechanical strength and toughness, which can resist severe cracking and crushing during cycling, thereby maintaining structural stability/integrity. As a result, the SbSn/NPC served as anode exhibits outstanding performance in sodium-ion half/full-cells, and endows SbSn/NPC||expanded graphite (EG) sodium-based dual-ion batteries (SDIBs) with superior energy/power density (136 Wh kg−1/2623 W kg−1) and persistent stability over ultralong cycling (99 mAh/g at 1.0 A/g after 1000 cycles). This work sheds new horizons to surmount the inherent boundedness of alloying-based materials for application in emerging energy storage devices.