Interfacial Covalent Bonding Endowing Ti3C2-Sb2S3 Composites High Sodium Storage Performance

Antimony sul?de is attracting enormous attention due to its remarkable theoretical capacity as anode for sodium-ion batteries (SIBs). However, it still suffers from poor structural stability and sluggish reaction kinetics. Constructing covalent chemical linkage to anchor antimony sul?de on two-dimension conductive materials is an effective strategy to conquer the challenges. Herein, Ti3C2-Sb2S3 composites are successfully achieved with monodispersed Sb2S3 uniformly pinned on the surface of Ti3C2Tx MXene through covalent bonding of Ti-O-Sb and S-Ti. Ti3C2Tx MXene serves as both charge storage contributor and flexible conductive buffer to sustain the structural integrity of the electrode. Systematic analysis indicates that construction of efficient interfacial chemical linkage could bridge the physical gap between Sb2S3 nanoparticles and Ti3C2Tx MXene, thus promoting the interfacial charge transfer efficiency. Furthermore, the interfacial covalent bonding could also effectively confine Sb2S3 nanoparticles and the corresponding reduced products on the surface of Ti3C2Tx MXene. Benefited from the unique structure, Ti3C2-Sb2S3 anode delivers a high reversible capacity of 475 mAh g(-1) at 0.2 A g(-1) after 300 cycles, even retaining 410 mAh g(-1) at 1.0 A g(-1) after 500 cycles. This strategy is expected to shed more light on interfacial chemical linkage towards rational design of advanced materials for SIBs.

Automated summary

This study successfully achieved Ti3C2-Sb2S3 composites by covalently bonding Sb2S3 uniformly on the surface of Ti3C2Tx MXene. The efficient interfacial chemical linkage bridged the physical gap and promoted the interfacial charge transfer efficiency, leading to a high reversible capacity and long cycling stability of the Ti3C2-Sb2S3 anode for sodium-ion batteries.