A wheat flour derived hierarchical porous carbon/graphitic carbon nitride composite for high-performance lithium–sulfur batteries. (December 2020)

• Record Type: Journal Article
• Authors: Hong, Xiaodong; Liu, Yue; Fu, Jiawei; Wang, Xu; Zhang, Tao; Wang, Sihui; Hou, Feng; Liang, Ji
• Is Part Of: Carbon. Volume 170(2020)
• Page Start: 119
• Page End: 126
• Publication Date: 2020-12
• Subjects: Hierarchical porous carbon -- Graphitic carbon nitride -- Li-S batteries -- Sulfur confinement; Carbon -- Periodicals; Carbone -- Périodiques; Koolstof; Toepassingen; Electronic journals; 546.681
• DOI: 10.1016/j.carbon.2020.08.032
• Languages: English
• ISSNs: 0008-6223

Abstract

Abstract: To buffer the volume variation of sulfur and suppress the shuttle effect of long-chain lithium polysulfides during the cycling of Li-S batteries, it is essential to simultaneously design suitable pore structures and tune the surface chemistry of carbon-based sulfur hosts. However, the associated low yield and high cost of such delicately constructed carbon materials have been the major bottleneck for their practical utilization. Herein, we present a hundred-gram fabrication of a graphitic carbon nitride@hierarchical porous carbon (g-C3 N4 @HPC) composite, which is derived from low-cost biomass and used as the sulfur host for Li-S batteries. On this material, interconnected and hierarchical porosity of HPC physically traps the polysulfides and buffers the volume variation, and in the meantime, the uniformly dispersed g-C3 N4 nanoparticles and N dopants on it provide strong chemical affinity to further immobilize the polysulfides. Therefore, the g-C3 N4 @HPC/S cathode delivers a high initial capacity of 1150.1 mAh g −1 and excellent cycling stability with a very small capacity decay of 0.024% cycle −1 for 250 cycles, at a high sulfur loading of 64.5 wt%. Importantly, this g-C3 N4 @HPC composite is derived from very cheap and eco-friendly precursors, enabling the hundred-gram production at bench-top scale, which shows significant viability for practical Li-S battery application. Graphical abstract: Wheat flour-derived porous carbon decorated with g-C3 N4 nanoparticles (g-C3 N4 @HPC) is developed as a sulfur host for high-performance Li-S batteries, which can be fabricated at hundred-gram scale via very a simple protocol. The hierarchical porosity and g-C3 N4 nanoparticles effectively inhibit the shuttling of soluble polysulfides by dual physical/chemical confinement. Image 1