Novel Sulfur/Ethylenediamine-Functionalized Reduced Graphene Oxide Composite as Cathode Material for High-performance Lithium-Sulfur Batteries

• Published in: Nanomaterials (Basel, Switzerland) Vol. 8; no. 5; p. 303
• Main Authors: Chen, Zhuo, Sun, Zhenghao, Zhang, Yongguang, Tan, Taizhe, Tian, Yuan, Chen, Zhihong
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 06.05.2018; MDPI
• Subjects: Cathodes; Composite materials; Discharge capacity; Electrochemical analysis; Electrochemistry; Electrode materials; Ethylenediamine; Graphene; Lithium; Lithium sulfur batteries; Morphology; Nanocomposites; Reducing agents; Sulfur; ethylenediamine; lithium-sulfur batteries; reduced graphene oxides
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano8050303

Sulfur/ethylenediamine-functionalized reduced graphene oxide (S/EDA-RGO) nanocomposites were synthesized using a simple process. Ethylenediamine (EDA) was employed as both the reducing agent and the modification component. The morphologies, microstructures, and compositions of S/EDA-RGO composites were characterized by various detection techniques. The data indicated that EDA-RGO used as scaffolds for sulfur cathodes could enhance the electronic conductivity of the composites and strengthen the adsorbability of polysulfides. Meanwhile, the electrochemical properties of both S/EDA-RGO and S/RGO composites that were used as cathodes for lithium-sulfur (Li-S) batteries were investigated. The initial discharge capacity of S/EDA-RGO composites reached 1240 mAh g , with reversible capacity being maintained at 714 mAh g after 100 cycles. The improvement in cycling stability of S/EDA-RGO composites was further verified at different current rates. These findings demonstrated that proper surface modification of RGO by EDA reducing agent might improve the electrochemical performances of Li⁻S batteries.