Enhancing the polysulfide redox conversion by a heterogeneous CoP-Co3S4 electrocatalyst for Li-S batteries

The development of lithium-sulfur (Li-S) batteries necessitates the creation of efficient cathode materials. By simultaneous phosphating and sulfurating, a spindle-shaped CoP-Co3S4 heterostructure sulfur cathode substrate made up of numerous tiny needle-like structures is created. The benefits of CoP with outstanding conductivity and Co3S4 with great adsorption capacity are combined in the as-prepared CoP-Co3S4 het-erostructures, which achieve efficient capture-diffusion-transformation of polysulfides at the interface. The CoP accelerates the redox kinetics toward polysulfide conversion, and the Co3S4 has a considerable ad-sorption power toward polysulfides. The quick nucleation of polysulfide and increased capture effectiveness are aided by the quick transfer of polysulfide from the Co3S4 surface to the CoP surface. As a result, the CoP-Co3S4 @S cathode battery with a 1.1 mg cm-2 sulfur load achieves a high initial capacity of 1516.9 mAh g-1 at 0.2 C and maintains that capacity after 100 cycles at 750.1 mAh g-1. After 300 cycles, even the 565.1 mAh g-1 specific capacity can be attained at 1 C.& COPY; 2023 Elsevier B.V. All rights reserved.

Automated summary

By simultaneous phosphating and sulfurating, a spindle-shaped CoP-Co3S4 heterostructure sulfur cathode substrate is created, which achieves efficient capture-diffusion-transformation of polysulfides at the interface. The CoP accelerates the redox kinetics toward polysulfide conversion, and the Co3S4 has a considerable ad-sorption power toward polysulfides. The CoP-Co3S4 @S cathode battery achieves a high initial capacity of 1516.9 mAh g-1 at 0.2 C and maintains that capacity after 100 cycles at 750.1 mAh g-1. After 300 cycles, even the 565.1 mAh g-1 specific capacity can be attained at 1 C.