Deciphering the defect micro‐environment of graphene for highly efficient Li–S redox reactions. Issue 3 (4th January 2022)

• Record Type: Journal Article
• Authors: Song, Yingze; Gao, Hua; Wang, Menglei; Chen, Le; Cao, Xuan; Song, Lixian; Liu, Xiaohong; Cai, Wenlong; Sun, Jingyu; Zhang, Wei
• Is Part Of: EcoMat. Volume 4:Issue 3(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-01-04
• Subjects: defect micro‐environment -- defective graphene -- lithium–sulfur battery -- plasma irradiation -- sulfur redox reaction kinetics; Materials -- Environmental aspects -- Periodicals; Clean energy -- Periodicals; 621.042
• DOI: 10.1002/eom2.12182
• Languages: English
• ISSNs: 2567-3173

Abstract

Abstract: The lithium polysulfides (LiPS) dissolution into electrolyte as well as consequent shuttle behavior seriously exacerbate the electrochemical performance of lithium–sulfur batteries. Herein, the intrinsic defect of graphene has been tailored by using plasma irradiation. The topological defective carbon structure is demystified into monovacancy and divacancy which effectively promote Li–S redox kinetics by selectively decelerating the generation of soluble high‐order LiPSs and passingly promoting the conversion to final solid products. Theoretical prediction uncovers the selective manipulation of Li–S redox kinetics by defective graphene, facilitating the reduced overpotential effect and uniform deposition of Li2 S. Moreover, the divacancy presents a higher activity for Li–S chemistry in contrast with monovacancy. Therefore, the battery achieves superior cyclability with a capacity retention of 88.6% at 1.0 C over 300 cycles. Furthermore, it yields an areal capacity up to 8.5 mAh cm −2 with a sulfur loading of 13.3 mg cm −2 . Abstract : The defect micro‐environment of graphene structure for highly efficient Li–S redox reactions is deciphered. The defective graphene, especially the divacancy one, exhibits catalyzed Li–S redox reaction kinetics by selectively decelerating the generation of high‐order LiPSs and passingly promoting the conversion to Li2 S solid products, shedding frontier light on practical Li–S batteries by designing specific defect‐type graphene structures.