Rational carbon design and confinement of leaf-like Tin trisulfide@Carbon/MXene Ti3C2Tx for enhanced conductivity and lithium storage kinetics

Abstract

Due to the abundant terrestrial storage of raw materials, tin sulfide stands out as one of the most promising candidates for anodes in lithium-ion batteries (LiBs). Among its various forms, Tin trisulfide (Sn₂S₃) is a n-type semiconductor with notable anisotropic electrical conductivity. However, research on Sn₂S₃ crystal materials and their utilization as anode materials in LiBs remains limited. To expand the scope of application research involving Sn₂S₃ anode materials and to address the efficiency shortcomings associated with tin sulfide, a novel stacked leaf-like Sn₂S₃@C/Ti₃C₂T_x anode material has been meticulously designed and synthesized. Employing mechanical ball milling, the negatively charged surface of the Ti₃C₂T_x material is strategically leveraged to create defect spaces. These spaces facilitate a more stable anchoring of Sn₂S₃@C onto the sheet-like surface, mitigating internal stresses that may arise during charge–discharge cycles due to material aggregation. When deployed as the anode in LiBs, the Sn₂S₃@C/Ti₃C₂T_x composite exhibits exceptional cycling stability and conductivity. Notably, it demonstrates high reversible specific capacities across various current densities, i.e., 1162, 996.8, 925.4, 866.4, 810.1, 721.4, 624.5, and 552.8 mAh g⁻¹ at 0.1, 0.2, 0.5, 1, 2, 4, 8, and 10 A g⁻¹, respectively, surpassing those reported for SnS_x-based anodes for LiBs. Additionally, dynamic tests such as galvanostatic intermittent titration technique (GITT) reveal that Sn₂S₃@C/Ti₃C₂T_x possesses superior surface diffusion capability and rapid electrical conduction rates. These findings underscore the significant potential for the practical application of Sn₂S₃@C/Ti₃C₂T_x nanocomposites in high-performance LiBs, offering a promising avenue for advancing battery technology towards enhanced efficiency and reliability.