A Sheet-like Carbon Matrix Hosted Sulfur as Cathode for High-performance Lithium-Sulfur Batteries

Abstract

Lithium-sulfur (Li-S) batteries are a promising candidate of next generation energy storage systems owing to its high theoretical capacity and energy density. However, to date, its commercial application was hindered by the inherent problems of sulfur cathode. Additionally, with the rapid decline of non-renewable resources and active appeal of green chemistry, the intensive research of new electrode materials was conducted worldwide. We have obtained a sheet-like carbon material (shaddock peel carbon sheets SPCS) from organic waste shaddock peel, which can be used as the conductive carbon matrix for sulfur-based cathodes. Furthermore, the raw materials are low-cost, truly green and recyclable. As a result, the sulfur cathode made with SPCS (SPCS-S), can deliver a high reversible capacity of 722.5 mAh g−1 at 0.2 C after 100 cycles with capacity recuperability of ~90%, demonstrating that the SPCS-S hybrid is of great potential as the cathode for rechargeable Li-S batteries. The high electrochemical performance of SPCS-S hybrid could be attributed to the sheet-like carbon network with large surface area and high conductivity of the SPCS, in which the carbon sheets enable the uniform distribution of sulfur, better ability to trap the soluble polysulfides and accommodate volume expansion/shrinkage of sulfur during repeated charge/discharge cycles.

Amylose-Derived Macrohollow Core and Microporous Shell Carbon Spheres as Sulfur Host for Superior Lithium–Sulfur Battery Cathodes

“…LSBs in recent years, including those from Apricot shell, 5 silk cocoon, 6 shaddock peel, 7 bamboo charcoal, 25 cotton 26 and pig bone, 27 etc. KOH assisted pyrolysis is the commonly used method for carbonization.…”

“…6,7,27 Hierarchically porous and microporous structures with surface areas of 900-3200 m 2 g -1 are achievable. 6,7,27 After incorporating sulfur contents of 50-68 wt%, those S@C hybrids 6,7,27 show favorable capacities and capacity retention. In addition, besides the application as porous carbon hosts for sulfur cathodes, biomass derived carbonaceous materials are also reported for other applications in LSBs.…”

“…A micron-sized spherical hierarchical porous carbon with macroporous core and microporous shell was obtained by the multi-step pyrolysis (the obtained carbon is abbreviated as MHPC) without oxide templates, which is commonly used in the synthesis of porous spherical carbon. 7,14 The carbon shows a high surface area and high porosity.…”

“…The broad peak at around 23 o and the relatively weak peak at around 43 o , corresponds to the (002) and 100reflections of pretended (what does this mean here ???) graphitic domains, 3,7 demonstrating partial graphitization of the carbon. In comparison, the spherical morphology of the raw amylose was completely destroyed after the one-step pyrolysis, showing a typically crushed shape after milling by agate mortar, and no pores are observed by SEM, as shown in Fig.…”

Inspired by the “tip effect”: a novel structural design strategy for the cathode in advanced lithium–sulfur batteries

“…Inltrating molten sulfur into porous conductive carbon materials was the main approach in the early stages. [9][10][11] This strategy can form interconnected conducting networks and enhance the physical entrapment of the lithium polysuldes (LiPS). [12][13][14] However, carbon hybrids are less effective in trapping LiPS because the chemical interactions between the nonpolar carbons and the polar polysuldes are rather weak.…”