Enhanced lithium-sulfur battery eilectrochemistry via Se-doped MoS2/rGO ultrathin sheets as sulfur hosts

• Published in: Applied surface science 2025-02, Vol.682, p.161718, Article 161718
• Main Authors: Zhu, Mengmeng, Zhang, Ying, Xu, Shixian, Yan, Xueli, Song, Yiming, Wang, Meili, Dong, Yutao, Zhang, Jianmin
• Format: Article
• Language: English
• Subjects: Lithium-sulfur battery; MoS2/rGO; Se-doping; Sulfur host; Ultrathin sheet
• ISSN: 0169-4332
• DOI: 10.1016/j.apsusc.2024.161718

In this research, surface engineering and heteroatom doping are leveraged to synthesize a high-surface-area, anion-doped MoS2-xSex/rGO nanosheet. The incorporation of selenium augments sulfur adsorption and catalytic activity, facilitating efficient sulfur conversion. The resulting lithium-sulfur battery demonstrates enhanced cyclability and superior rate performance when employing the Se-doped MoS2/rGO ultrathin sheet as a sulfur host. [Display omitted] •The Se-doped MoS2 in-situ grows on the rGO surface to form a MoS2-xSex/rGO ultrathin sheet using a hydrothermal technology.•The introduction of Se in the 2D ultrathin sheet can not only increase the adsorption of LiPSs, but also improve the catalytic activity.•The Li-S battery with the sulfur host of MoS1.94Se0.06/rGO displays an extraordinary coulombic efficiency and cycle stability. In the pursuit of advancing lithium-sulfur (Li-S) battery technology, the intrinsic challenges of sulfur conductivity and the shuttle effect during charge-discharge cycles have posed significant barriers. Despite many efforts made through physical and chemical methodologies, the development of host materials with more active sites and good catalytic activities might still remain a challenging problem in Li-S batteries. This study presents a novel selenium-doped molybdenum disulfide (Se-MoS2) nanosheet, synthesized on reduced graphene oxide (rGO), which would address these issues. The Se-MoS2/rGO composite enhances conductivity and catalytic activity through the creation of anionic vacancies, facilitating lithium polysulfide adsorption. As a sulfur host, this material delivers an impressive initial capacity of 1008.1 mAh g−1 at 1C, maintaining 620.7 mAh g−1 after 500 cycles with a minimal capacity fade of 0.077 % per cycle, demonstrating superior coulombic efficiency and stability. The findings underscore the impact of heteroatom doping on the electrochemical performance of graphene-based materials for Li-S batteries.