Corn stalk-derived activated carbon with a stacking sheet-like structure as sulfur cathode supporter for lithium/sulfur batteries

Abstract

A novel stacking sheet-like carbon (SSC) has been synthesized by carbonizing the corn stalks and composited with sulfur to prepare a cathode for lithium/sulfur batteries. Scanning electronic microscopy observations showed the formation of irregularly interlaced nanosheet-like structure consisting SSC with uniform sulfur coating on its surface. The SSC nanoflakes in the composite act as nanocurrent collectors, favoring the charge carrier ion transport and electrolyte diffusion. The interlaced SSC nanoflakes irregularly stack together and form a three-dimensional network, which is beneficial for both trapping soluble polysulfide intermediates and rendering the electrical conductivity of the composite electrode. A lithium cell employing this sulfur/stacking sheetlike carbon (S/SSC) composite cathode delivered an initial discharge capacity of 965 mAh g −1 at 0.2 C and retained a capacity of 743 mAh g −1 over 100 charge-discharge cycles.Even at 3.2 C rate, the lithium cell with the S/SSC composite cathode demonstrated an excellent rate capability, delivering a highly reversible discharge capacity of 418 mAh g −1.

Ternary Sulfur/Polyacrylonitrile/SiO2 Composite Cathodes for High-Performance Sulfur/Lithium Ion Full Batteries

“…Lithium/sulfur (Li/S) batteries have high theoretical energy densities reaching up 2600 Wh kg −1 , making them the most promising energy chemical power systems. In regard to this, elemental sulfur as cathode has low cost when combined with its environmental friendliness and high theoretical specific capacity (1672 mAh g −1 ) [13,14,15,16,17,18]. However, despite these criteria, the development of Li/S batteries still faces numerous challenges.…”

Biomass-derived nanostructured porous carbons for lithium-sulfur batteries

“…In physical or thermal activation, the pyrolyzed carbon is exposed to an oxidizing atmosphere (such as CO 2 , steam or a mixture of both) in the temperature range of 600-1200°C and the porosity is developed by partial etching of the carbon. On the other hand, in chemical activation the carbon precursor is mixed with some chemicals such as NaOH [39], KOH [40][41][42][43][44][45][46][47][48], ZnCl 2 [5,[49][50][51], H 3 PO 4 [52][53][54] and H 2 SO 4 [3,55], and then carbonization and activation are accomplished simultaneously at a slightly lower temperature ranged within 300-950°C. Of the activating agents, KOH is the most promising because it can produce nanostructured porous carbons with higher yields at lower temperature, and produce materials with ultrahigh specific surface area up to 3000 m 2 g −1 with a well-defined pore size distribution.…”

Biomass-derived activated carbon/sulfur composites as cathode electrodes for Li–S batteries by reducing the oxygen content

“…2 However, the large-scale commercial application of Li-S batteries is still hindered by the low electrical conductivity of sulfur, the shuttle effect and serious volumetric change of lithium polysuldes and sulfur. 3,4 To overcome those problems, tremendous efforts have been exerted to improve the electrochemical performance of Li-S batteries. One of the most effective and promising ways is to fabricate sulfur/carbon composites, as the porous carbon has a high electronic conductivity, which could overcome the electrical insulation of sulfur and intermediate polysuldes.…”