Rich Heterointerfaces Enabling Rapid Polysulfides Conversion and Regulated Li₂S Deposition for High-Performance Lithium–Sulfur Batteries

Abstract

The practical uses of lithium–sulfur batteries are greatly restricted by the sluggish reaction kinetics of lithium polysulfides (LiPSs), leading to low sulfur utilization and poor cyclic stability. Using the heterostructure catalysts is an effective way to solve the above problems, but how to further enhance the conversion efficiency and avoid the surface passivation by the insulative Li2S has not been well investigated. Herein, a heterostructure catalyst with rich heterointerfaces was prepared by modifying Mo2N microbelt with SnO2 nanodots. The formed rich interfaces with high accessibility act as the profitable nucleation sites guiding the Li2S 3D growth, which avoids the catalyst surface passivation and facilitates the LiPS conversion. The introduction of SnO2 nanodots also enhances the LiPS adsorption. Thus, the assembled battery with the above catalyst as the cathode additive shows a high capacity of 738.3 mAh g–1 after 550 cycles at 0.5 C with an ultralow capacity decay of 0.025% per cycle. Even with high sulfur loading of 9.0 mg cm–2, good cyclic stability is also achieved at 0.5 C with a low E/S ratio of 5 μL mgs –1. This work shows an effective way to enhance the LiPS conversion kinetics and guide Li2S deposition in Li–S batteries.

Implanting Single Zn Atoms Coupled with Metallic Co Nanoparticles into Porous Carbon Nanosheets Grafted with Carbon Nanotubes for High‐Performance Lithium‐Sulfur Batteries

“…It is noticed that S@Co/SA-Zn@N-C/CNTs electrode delivered a high initial capacity of 932 mAh g −1 and maintained a high capacity of 680 mAh g −1 after 800 cycles with a low capacity decay rate of 0.033% per cycle, which not only outperform those of S@Co@N-C/CNTs, S@SA-Zn@N-C, and S@N-C electrodes but also are superior to most developed TM/C/S cathodes (Figure 3e). [36][37][38][39][40][41][42][43][44][45][46][47] A large areal sulfur mass loading is crucial for the real application of Li-S batteries. We further investigated the cycle performance of S@Co/SA-Zn@N-C/CNTs cathode with increased sulfur loading.…”

CoNiO2/Co4N Heterostructure Nanowires Assisted Polysulfide Reaction Kinetics for Improved Lithium–Sulfur Batteries

“…Considering the conductivity of CoNiO 2 and graphene, the polarization difference fully indicated that CoNiO 2 had a good catalytic function of polysulfides. [44] Meanwhile, the corresponding Tafel plots and slopes of all peaks were also calculated to quantify the catalytic activities (Figure 5b,c and Figure S11, Supporting Information). Evidently, the CoNiO 2 /Co 4 N-G-S electrode exhibited the lowest slopes at the oxidation of Li 2 S and the reduction of sulfur to long-chain sulfur species, implying the greatest improvement in the kinetics.…”

Boosting Polysulfide Catalytic Conversion and Facilitating Li+ Transportation by Ion‐Selective COFs Composite Nanowire for LiS Batteries

“…This indicates the active sites of C@COF surface could guide the radical Li 2 S growth and the surface passivation can be avoided. [54,55] when using the CNTs, Li 2 S growth shows a tendency to 2DI model, which formed a uniform Li 2 S nucleation and made its surface easily passivated. [52] The Li 2 S dissolution kinetics was also evaluated.…”