Rongmei Zhu, Yuxuan Jiang, Bingxin Sun, Wang Zhang, Huan Pang
{"title":"MOF-derived Co–Mo bimetallic heterostructures for the selective trapping and conversion of polysulfides in lithium–sulfur batteries","authors":"Rongmei Zhu, Yuxuan Jiang, Bingxin Sun, Wang Zhang, Huan Pang","doi":"10.1039/d4qi01249f","DOIUrl":null,"url":null,"abstract":"Lithium–sulfur batteries (LSBs) are promising energy storage systems, but their practical application is hindered by the polysulfide shuttle effect and slow redox kinetics. To address these challenges, we constructed ZIF-67@CoS<small><sub><em>x</em></sub></small>/MoO<small><sub>3</sub></small> with a core–shell structure and CoS<small><sub><em>x</em></sub></small>/MoO<small><sub>3</sub></small> with a hollow structure as separator-modified materials for LSBs by varying the degree of sulfidation of ZIF-67. The high intrinsic conductivity of CoS<small><sub><em>x</em></sub></small> facilitated ion transfer between the cathode and separator. Additionally, the introduction of MoO<small><sub>3</sub></small> formed a heterogeneous structure with CoS<small><sub><em>x</em></sub></small> that enhanced the adsorption of LiPSs. <em>Via in situ</em> UV-vis and electrochemical impedance spectroscopy testing, we demonstrated the preferred selective trapping and conversion of LiPSs by CoS<small><sub><em>x</em></sub></small>/MoO<small><sub>3</sub></small>. As a result of the synergistic effect of the bimetallic heterogeneous structure, the modified LSB exhibited excellent cycling stability, with a capacity decay rate of only 0.041% after 500 cycles at 1C. Moreover, it achieved a high discharge capacity of 632 mA h g<small><sup>−1</sup></small> at 2C. This work provides a novel concept for MOF-derived heterogeneous structures to be applied in high-performance LSBs.","PeriodicalId":79,"journal":{"name":"Inorganic Chemistry Frontiers","volume":null,"pages":null},"PeriodicalIF":6.1000,"publicationDate":"2024-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Inorganic Chemistry Frontiers","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1039/d4qi01249f","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, INORGANIC & NUCLEAR","Score":null,"Total":0}
引用次数: 0
Abstract
Lithium–sulfur batteries (LSBs) are promising energy storage systems, but their practical application is hindered by the polysulfide shuttle effect and slow redox kinetics. To address these challenges, we constructed ZIF-67@CoSx/MoO3 with a core–shell structure and CoSx/MoO3 with a hollow structure as separator-modified materials for LSBs by varying the degree of sulfidation of ZIF-67. The high intrinsic conductivity of CoSx facilitated ion transfer between the cathode and separator. Additionally, the introduction of MoO3 formed a heterogeneous structure with CoSx that enhanced the adsorption of LiPSs. Via in situ UV-vis and electrochemical impedance spectroscopy testing, we demonstrated the preferred selective trapping and conversion of LiPSs by CoSx/MoO3. As a result of the synergistic effect of the bimetallic heterogeneous structure, the modified LSB exhibited excellent cycling stability, with a capacity decay rate of only 0.041% after 500 cycles at 1C. Moreover, it achieved a high discharge capacity of 632 mA h g−1 at 2C. This work provides a novel concept for MOF-derived heterogeneous structures to be applied in high-performance LSBs.