Electrocatalysis in Lithium Sulfur Batteries under Lean Electrolyte Conditions

• DOI: 10.1002/ange.201808311
• Publication Date: 2018-09-26T01:49:28Z
• Authors: Yuxiang Yang; Yiren Zhong; Qiuwei Shi; Zhenhua Wang; Kening Sun; Hailiang Wang
• Keywords: 7. Clean energy; 3. Good health

AbstractThe presence of electrocatalysis in lithium–sulfur batteries has been proposed but not yet sufficiently verified. In this study, molybdenum phosphide (MoP) nanoparticles are shown to play a definitive electrocatalytic role for the sulfur cathode working under lean electrolyte conditions featuring a low electrolyte/active material ratio: the overpotentials for the charging and discharging reactions are greatly decreased. As a result, sulfur electrodes containing MoP nanoparticles show faster kinetics and more reversible conversion of sulfur species, leading to improvements in charging/discharging voltage profiles, capacity, rate performance, and cycling stability. Taking advantage of the electrocatalytic properties of MoP, high‐performance sulfur electrodes were successfully realized that are steadily cyclable at a high areal capacity of 5.0 mAh cm−2 with a challenging electrolyte/sulfur (E/S) ratio of 4 μLE mg−1S .