{"title":"Ultrafine Mo2N Quantum Dots Embedded in N-Doped Graphene Sheets Enable Efficient Adsorption-Catalytic Transformation of Polysulfides","authors":"Jiahang Fan, Pei Su, Taotao Guo, Mingwei Liu, Tianyu Huo, Henan Jia","doi":"10.1021/acsami.4c13328","DOIUrl":null,"url":null,"abstract":"Because of the high theoretical energy density of 2600 Wh kg<sup>–1</sup>, lithium–sulfur batteries (LSBs) are anticipated to be among the next generation of high-energy-density storage technologies. However, the practical application of LSBs has been severely hampered by the significant shuttle effect and slow redox kinetics of polysulfides (LiPSs). To address the above problems, in this paper, the concept of quantum dots (QDs) was introduced to design and synthesize Mo<sub>2</sub>N QD-modified N-doped graphene nanosheets (marked as Mo<sub>2</sub>N-QDs@NG), which were used as separator modification materials for LSBs. The experimental results demonstrated that the introduction of Mo<sub>2</sub>N QDs avoids stacking of graphene sheets and provides more active sites for the conversion of LiPSs. Moreover, Mo<sub>2</sub>N enhances the chemical fixation and catalyzes the liquid–solid conversion of soluble LiPSs by forming Mo–S and Li–N bonds with LiPSs. Additionally, establishing Mo–C bonds with Mo<sub>2</sub>N, N-doped graphene sheets can facilitate the transport of electrons and ions and physically prevent the diffusion of LiPSs, thus creating a highly conducting carbon structure to support electrochemical reactions. Benefiting from the synergistic effect of chemical immobilization and catalysis of Mo<sub>2</sub>N QDs with the physical confinement of NG, Mo<sub>2</sub>N-QDs@NG-PP batteries exhibit enhanced electrochemical performance.","PeriodicalId":5,"journal":{"name":"ACS Applied Materials & Interfaces","volume":null,"pages":null},"PeriodicalIF":8.3000,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Applied Materials & Interfaces","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.1021/acsami.4c13328","RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Because of the high theoretical energy density of 2600 Wh kg–1, lithium–sulfur batteries (LSBs) are anticipated to be among the next generation of high-energy-density storage technologies. However, the practical application of LSBs has been severely hampered by the significant shuttle effect and slow redox kinetics of polysulfides (LiPSs). To address the above problems, in this paper, the concept of quantum dots (QDs) was introduced to design and synthesize Mo2N QD-modified N-doped graphene nanosheets (marked as Mo2N-QDs@NG), which were used as separator modification materials for LSBs. The experimental results demonstrated that the introduction of Mo2N QDs avoids stacking of graphene sheets and provides more active sites for the conversion of LiPSs. Moreover, Mo2N enhances the chemical fixation and catalyzes the liquid–solid conversion of soluble LiPSs by forming Mo–S and Li–N bonds with LiPSs. Additionally, establishing Mo–C bonds with Mo2N, N-doped graphene sheets can facilitate the transport of electrons and ions and physically prevent the diffusion of LiPSs, thus creating a highly conducting carbon structure to support electrochemical reactions. Benefiting from the synergistic effect of chemical immobilization and catalysis of Mo2N QDs with the physical confinement of NG, Mo2N-QDs@NG-PP batteries exhibit enhanced electrochemical performance.
期刊介绍:
ACS Applied Materials & Interfaces is a leading interdisciplinary journal that brings together chemists, engineers, physicists, and biologists to explore the development and utilization of newly-discovered materials and interfacial processes for specific applications. Our journal has experienced remarkable growth since its establishment in 2009, both in terms of the number of articles published and the impact of the research showcased. We are proud to foster a truly global community, with the majority of published articles originating from outside the United States, reflecting the rapid growth of applied research worldwide.