Lee, Youn-Ki Lee, Cheol-Ho Lee, Hea Ri Lee, Gwanwon Joh, Han-Ik Lee, Sungho 2024-03-07T02:30:16Z 2024-03-07T02:30:16Z 2024-03-07 2024-02 1385-8947 https://pubs.kist.re.kr/handle/201004/149400 Molybdenum sulfides are highly regarded as conversion-type electrodes with exceptional performance potential in lithium-ion batteries (LIBs). However, elucidating their lithium (Li) storage behavior has proven challenging due to the intricate sulfur (S) coordination with molybdenum atoms, which has impeded the realization of high energy densities in future Li storage systems. In this study, we investigate the electrochemical redox reaction pathways of molybdenum sulfide, specifically exploring the impact of various S configurations, including terminal, bridging, and apical S. We employ a comprehensive approach, involving extensive electrochemical measurements and depth X-ray photoelectron spectroscopy (XPS) profiling. In contrast to the multi-step conversion reactions observed in MoS2, sulfur-enriched molybdenum sulfides exhibit a unique single-step Li-ion storage mechanism. As a consequence of the pronounced effect of S configuration on the activation energy barrier during charging and discharging, the redox reaction voltage with Li ions exhibits variations. This versatility verifies that molybdenum sulfides have the potential to serve as both anode and cathode materials in lithium-ion batteries. Furthermore, we propose the incorporation of reduced graphene oxide (rGO) composites to address inherent limitations of molybdenum sulfides, including low electrical conductivity and irreversible reactions. The robust interaction between molybdenum sulfides and oxygen functional groups in rGO enhances rate capability and ensures a stable cycling lifespan. Through this systematic investigation, we suggest a comprehensive insight into the electrochemical reaction pathways governing Li storage behavior in molybdenum sulfides with distinct S configurations. This contributes to the fundamental understanding of these materials and their potential applications in advanced energy storage systems. English Elsevier BV Understanding the influence of sulfur configuration on the electrochemical reaction pathway for lithium storage in molybdenum sulfides Article 10.1016/j.cej.2024.148672 1 Chemical Engineering Journal, v.481 Chemical Engineering Journal 481 N scie scopus 001167133500001 2-s2.0-85182891486 Engineering, Environmental Engineering, Chemical Engineering Article HYDROGEN-EVOLUTION CATALYST CONVERSION REACTIONS MOS2 ELECTRODE HIGH-CAPACITY MECHANISM NANOCOMPOSITES DISULFIDE THIOMOLYBDATE PERFORMANCE BATTERIES depth XPS Lithium storage behavior Molybdenum sulfides Sulfur configuration