Wrinkled sulfur@graphene microspheres with high sulfur loading as superior-capacity cathode for LiS batteries. (October 2016)

• Record Type: Journal Article
• Authors: He, Jiarui; Zhou, Keren; Chen, Yuanfu; Xu, Chen; Lin, Jie; Zhang, Wanli
• Is Part Of: Materials today energy. Volume 1/2(2016)
• Page Start: 11
• Page End: 16
• Publication Date: 2016-10
• Subjects: Graphene -- Lithium sulfur battery -- Wrinkled microspheres; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2016.10.001
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: For the first time, wrinkled sulfur@graphene microspheres (WSGM) with very high mass (82.3 wt%) and areal (2.0 mg cm −2 ) sulfur loading, constructed with sulfur nanoparticles wrapped by N-doped graphene nanosheets, have been synthesized through a facile spray drying route. When WSGM is used as the cathode for lithium-sulfur (LiS) cells, it delivers superior electrochemical performance: the reversible specific capacity at 0.1C is as large as 1165.7 mAh g −1 ; even after 200 cycles, the specific capacity at 0.2C remains 954.5 mAh g −1 with a high capacity retention of 82.9%; the C-rate capacities at 1, 2, and 4C are 735.1, 605, and 440.3 mAh g −1, respectively. The excellent performance is attributed to its unique wrinkled architecture: the N-doped graphene matrix guarantees its high conductivity for better electron and ion kinetics; the unique porous, wrinkled and flexible microsphere structure can not only provide abundant active sites to host sulfur and enhance the adsorption of soluble lithium polysulfides intermediates, but also effectively accommodate the volume variation of sulfur during lithiation. The spray drying strategy is facile, effective, and easily realized the large-scale and low-cost industrial production for graphene-sulfur composite cathode, which can be extended to produce other high-capacity electrode materials. Graphical abstract: Highlights: Wrinkled sulfur@graphene microspheres (WSGM) was synthesized by spray drying route. WSGM cathode with 82.3 wt% sulfur delivers superior electrochemical performance. Excellent performance is attributed to N-doping and unique wrinkled architecture.