Structurally Mutualized Ti3C2@Ni2P Catalysts Realize Interfacial Charge Redistribution for Facilitating Redox Reaction Kinetics in Lithium–Sulfur Batteries

The sluggish redox reaction kinetics of polysulfides (LiPSs) seriously hinders the performance of lithium-sulfur batteries (LSBs). To effectively accelerate the conversion of sulfur species, constructing heterostructure catalysts has emerged as a promising strategy. In this research, the Ti3C2@Ni2P electrocatalysts heterostructured with mutual structural support were fabricated by a straightforward phosphorylation method. The synergistic integration of the Ti3C2 substrate and uniformly distributed Ni2P particles solves the component agglomeration and stacking, accordingly, exposing more active sites and effectively anchoring LiPSs. Moreover, the built-in electric field could be formed between the heterointerfaces to promote the transfer of Li+/e-, reducing the energy barriers for LiPSs redox. Based on these advantages, LSBs assembled with Ti3C2@Ni2P catalysts could achieve an initial capacity of 1180 mAh g-1 at 0.2 C and a cycling decay rate of only 0.031% after 1000 cycles at 1 C. Besides, an area capacity of 4.0 mAh cm-2 was achieved even at a sulfur loading of 6.1 mg cm-2.