{"title":"Accelerating Sulfur Conversion Kinetics via CoS2-MgS Heterostructure for Lithium Sulfur Batteries","authors":"xinliang Men, teng Deng, Jiangxuan Che, Juan Wang","doi":"10.1039/d4ta06086e","DOIUrl":null,"url":null,"abstract":"The ultra-high theoretical specific capacity of sulfur (1672 mAh g-1) has attracted researchers to intensely explore lithium-sulfur batteries. However, the shuttle effect of polysulfides and the slow conversion kinetics of sulfur have hindered its advancement. Herein, we synthesized CoS2-MgS heterostructure catalysts deposited on acetylene black nanoparticles, which were used as separator coatings to improve lithium-sulfur battery performance. Various experiments, such as XPS, Tafel curves, Li2S6 symmetric cells, Li2S deposition, and DFT calculations, identified the advantages of the CoS2-MgS heterostructure: rapid polar adsorption of CoS2 to polysulfides through oxidized partial Co2+ to Co3+ and fast lithium-ion migration in MgS. The coin cells delivered an initial discharge capacity of 573.4 mAh g-1 and cycled stably for 600 cycles at 5 C with a capacity decay rate of 0.08% per cycle; The battery retained a specific capacity of 545.5 mAh g-1 (4.3 mAh cm-2) after 100 cycles at 0.1 C with a sulfur loading of 7.87 mg cm-2. In addition, laminated pouch cells with a sulfur of 311.5 mg exhibited excellent cycle stability, maintaining 768.3 mAh g-1 (239 mAh) after 80 cycles. This work provides ideas to find novel composites that have both fast lithium-ion migration and strong polar adsorption for sulfur conversion while providing a reference for pouch battery research.","PeriodicalId":82,"journal":{"name":"Journal of Materials Chemistry A","volume":null,"pages":null},"PeriodicalIF":10.7000,"publicationDate":"2024-10-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Materials Chemistry A","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1039/d4ta06086e","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The ultra-high theoretical specific capacity of sulfur (1672 mAh g-1) has attracted researchers to intensely explore lithium-sulfur batteries. However, the shuttle effect of polysulfides and the slow conversion kinetics of sulfur have hindered its advancement. Herein, we synthesized CoS2-MgS heterostructure catalysts deposited on acetylene black nanoparticles, which were used as separator coatings to improve lithium-sulfur battery performance. Various experiments, such as XPS, Tafel curves, Li2S6 symmetric cells, Li2S deposition, and DFT calculations, identified the advantages of the CoS2-MgS heterostructure: rapid polar adsorption of CoS2 to polysulfides through oxidized partial Co2+ to Co3+ and fast lithium-ion migration in MgS. The coin cells delivered an initial discharge capacity of 573.4 mAh g-1 and cycled stably for 600 cycles at 5 C with a capacity decay rate of 0.08% per cycle; The battery retained a specific capacity of 545.5 mAh g-1 (4.3 mAh cm-2) after 100 cycles at 0.1 C with a sulfur loading of 7.87 mg cm-2. In addition, laminated pouch cells with a sulfur of 311.5 mg exhibited excellent cycle stability, maintaining 768.3 mAh g-1 (239 mAh) after 80 cycles. This work provides ideas to find novel composites that have both fast lithium-ion migration and strong polar adsorption for sulfur conversion while providing a reference for pouch battery research.
期刊介绍:
The Journal of Materials Chemistry A, B & C covers a wide range of high-quality studies in the field of materials chemistry, with each section focusing on specific applications of the materials studied. Journal of Materials Chemistry A emphasizes applications in energy and sustainability, including topics such as artificial photosynthesis, batteries, and fuel cells. Journal of Materials Chemistry B focuses on applications in biology and medicine, while Journal of Materials Chemistry C covers applications in optical, magnetic, and electronic devices. Example topic areas within the scope of Journal of Materials Chemistry A include catalysis, green/sustainable materials, sensors, and water treatment, among others.